refactor: 移除 CueBanner 类及相关按钮，优化界面布局

- 删除 CueBanner.cs 文件，移除输入框的占位提示功能。
- 更新 MainForm.cs 和 MainFormUi.cs，删除与 Browse 按钮相关的代码，简化用户界面。
- 调整控件布局以提升整体用户体验，确保界面更加简洁。

TfsExcelImporter/Theme.cs

@@ -1,6 +1,8 @@
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 using System.Drawing.Drawing2D;
+using System.Runtime.InteropServices;
 using System.Windows.Forms;
 
 namespace TfsExcelImporter
@@ -149,10 +151,64 @@ namespace TfsExcelImporter
             return Card;
         }
 
-        public static int TextWidth(string text, Font font)        {
+        private static readonly Dictionary<int, SolidBrush> _eraseBrushes = new Dictionary<int, SolidBrush>();
+
+        /// <summary>
+        /// WM_ERASEBKGND 的快速擦除：直接用 GDI 把客户区铺成底色，不经过双缓冲、不建 GraphicsPath。
+        /// 自绘控件为了不闪都不擦背景，代价是窗口被重新暴露（还原、切前台）时那块像素保持系统的黑色，
+        /// 要等完整首帧（实测整窗 100ms+）才盖掉——这就是「黑色界面闪现」的来源。
+        /// 这里先用一次 FillRect 换掉黑底：即使完整首帧还没来，用户看到的也只是和界面同色的浅底。
+        /// </summary>
+        public static bool FastErase(IntPtr hwnd, IntPtr hdc, Color color)
+        {
+            RECT rc;
+            if (color.A == 0 || !GetClientRect(hwnd, out rc) || rc.right <= 0 || rc.bottom <= 0) return false;
+            int key = color.ToArgb();
+            SolidBrush brush;
+            if (!_eraseBrushes.TryGetValue(key, out brush))
+            {
+                brush = new SolidBrush(color);
+                _eraseBrushes[key] = brush;
+            }
+            var g = Graphics.FromHdc(hdc);
+            try { g.FillRectangle(brush, 0, 0, rc.right, rc.bottom); }
+            finally { g.Dispose(); }
+            return true;
+        }
+
+        [StructLayout(LayoutKind.Sequential)]
+        private struct RECT { public int left, top, right, bottom; }
+
+        [DllImport("user32.dll")]
+        private static extern bool GetClientRect(IntPtr hWnd, out RECT rc);
+
+        private static readonly Dictionary<string, int> _textWidths = new Dictionary<string, int>();
+
+        public static int TextWidth(string text, Font font)
+        {
             if (string.IsNullOrEmpty(text)) return 0;
-            return TextRenderer.MeasureText(text, font, Size.Empty,
+            // 排版会反复量同一批文案（拖拽缩放每帧都要全量量一遍），而 MeasureText 每次都要建 DC、选字体，
+            // 和查一次字典差两个数量级。字体是静态单例，键里带字体名/字号/字形就足以区分。
+            string key = font.Name + "|" + font.SizeInPoints.ToString("F1") + "|" + (int)font.Style + "|" + text;
+            int w;
+            if (_textWidths.TryGetValue(key, out w)) return w;
+            w = TextRenderer.MeasureText(text, font, Size.Empty,
                 TextFormatFlags.NoPadding | TextFormatFlags.SingleLine).Width;
+            if (_textWidths.Count > 800) _textWidths.Clear();   // 日志摘要/路径是动态文案，别让它无限涨
+            _textWidths[key] = w;
+            return w;
+        }
+
+        /// <summary>
+        /// 位置尺寸都没变就不动。每次 SetBounds 都是一次 WM_WINDOWPOSCHANGED 加一次重绘，
+        /// 而重排里绝大多数控件其实待在原地——打字、状态刷新这类重排尤其如此，
+        /// 拦掉空转会把这些场景的 70~100ms 直接抹平。
+        /// </summary>
+        public static void Place(Control c, int x, int y, int w, int h)
+        {
+            var b = c.Bounds;
+            if (b.X == x && b.Y == y && b.Width == w && b.Height == h) return;
+            c.SetBounds(x, y, w, h);
         }
 
         public static Color ChipInk(ChipKind kind)
@@ -393,6 +449,8 @@ namespace TfsExcelImporter
             g.SmoothingMode = SmoothingMode.AntiAlias;
             var r = new RectangleF(0.5f, 0.5f, Width - 1f, Height - 1f);
             using (var b = new SolidBrush(fill)) g.FillEllipse(b, r);
+            if (Kind == BadgeKind.Pending)
+                using (var p = new Pen(Theme.BorderStrong, Theme.Hair)) g.DrawEllipse(p, r);
             g.SmoothingMode = old;
             // 勾画在圆内缩 4px（14px 盒子 / 22px 圆），铺满整圆会贴边看着像被裁掉
             if (Kind == BadgeKind.Done) Icons.Draw(g, IconKind.Check, Icons.BadgeGlyph(ClientRectangle), ink);
@@ -423,6 +481,16 @@ namespace TfsExcelImporter
             TabStop = false;
         }
 
+        protected override void WndProc(ref Message m)
+        {
+            if (m.Msg == 0x0014 && Theme.FastErase(m.HWnd, m.WParam, BackColor))
+            {
+                m.Result = (IntPtr)1;
+                return;
+            }
+            base.WndProc(ref m);
+        }
+
         protected override void OnPaint(PaintEventArgs e)
         {
             Theme.FillPanel(e.Graphics, new Rectangle(0, 0, Width, Height), _face, LineColor,
@@ -446,6 +514,8 @@ namespace TfsExcelImporter
         public bool ShowBadge = true;
         /// <summary>卡片头部右侧留给按钮的宽度，摘要文字不越过它。</summary>
         public int HeaderReserve = 0;
+        /// <summary>头部摘要按「圆点 + 短语」分段绘制（状态摘要样式）；默认纯文本。</summary>
+        public bool SummaryDots = false;
         public int HeaderH = 44;
         public int BodyH = 0;
         public Action<bool> OnToggle;
@@ -461,6 +531,17 @@ namespace TfsExcelImporter
             HeaderH = Theme.Px(44);
         }
 
+        // 卡片占了大半客户区，窗口重新暴露时它不擦背景就是一大片黑——和 MainForm 一样先铺面色。
+        protected override void WndProc(ref Message m)
+        {
+            if (m.Msg == 0x0014 && Theme.FastErase(m.HWnd, m.WParam, BackColor))
+            {
+                m.Result = (IntPtr)1;
+                return;
+            }
+            base.WndProc(ref m);
+        }
+
         public Rectangle BodyRect { get { return new Rectangle(0, HeaderH, Width, BodyH); } }
 
         private Rectangle HeaderRect { get { return new Rectangle(0, 0, Width, HeaderH); } }
@@ -570,6 +651,10 @@ namespace TfsExcelImporter
                 var old = g.SmoothingMode;
                 g.SmoothingMode = SmoothingMode.AntiAlias;
                 using (var b = new SolidBrush(badgeFill)) g.FillEllipse(b, badge);
+                // 未激活徽章加一圈浅描边：纯灰底在白卡上存在感太弱，描边后与「激活/完成」的实心徽章同属一套语义
+                if (Badge == BadgeKind.Pending)
+                    using (var p = new Pen(Theme.BorderStrong, Theme.Hair))
+                        g.DrawEllipse(p, badge.X + 0.5f, badge.Y + 0.5f, badge.Width - 1f, badge.Height - 1f);
                 g.SmoothingMode = old;
                 if (Badge == BadgeKind.Done) Icons.Draw(g, IconKind.Check, Icons.BadgeGlyph(badge), badgeInk);
                 else
@@ -588,11 +673,15 @@ namespace TfsExcelImporter
                 | TextFormatFlags.SingleLine | TextFormatFlags.EndEllipsis);
 
             int sx = titleRect.Right + Theme.Px(12);
-            var sumRect = new Rectangle(sx, 0, Math.Max(0, Width - chevW - sx - Theme.Px(12)), HeaderH);
-            TextRenderer.DrawText(g, Summary, Theme.Caption, sumRect,
-                Invalid ? Theme.Danger : Theme.Ink2,
-                TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.NoPadding
-                | TextFormatFlags.SingleLine | TextFormatFlags.EndEllipsis);
+            int sumW = Math.Max(0, Width - chevW - sx - Theme.Px(12));
+            if (SummaryDots)
+                DrawDotSummary(g, Summary, sx, sumW);
+            else
+                TextRenderer.DrawText(g, Summary, Theme.Caption,
+                    new Rectangle(sx, 0, sumW, HeaderH),
+                    Invalid ? Theme.Danger : Theme.Ink2,
+                    TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.NoPadding
+                    | TextFormatFlags.SingleLine | TextFormatFlags.EndEllipsis);
 
             if (Collapsible)
             {
@@ -605,6 +694,40 @@ namespace TfsExcelImporter
                 using (var p = new Pen(Theme.Border))
                     g.DrawLine(p, Theme.S16, HeaderH, Width - Theme.S16, HeaderH);
         }
+
+        /// <summary>「圆点 + 短语」状态摘要：按 " · " 分段，每段一枚圆点；放不下的段整段省略。</summary>
+        private void DrawDotSummary(Graphics g, string summary, int x, int availW)
+        {
+            if (string.IsNullOrEmpty(summary) || availW <= 0) return;
+            var segments = summary.Split(new[] { " · " }, StringSplitOptions.None);
+            int dot = Theme.Px(6);
+            int dotGap = Theme.Px(6);
+            int segGap = Theme.Px(14);
+            int cursor = x;
+            int limit = x + availW;
+            foreach (var segment in segments)
+            {
+                if (cursor + dot + dotGap > limit) break;
+                var oldSmoothing = g.SmoothingMode;
+                g.SmoothingMode = SmoothingMode.AntiAlias;
+                using (var b = new SolidBrush(Invalid ? Theme.Danger : Theme.Ink3))
+                    g.FillEllipse(b, cursor, (HeaderH - dot) / 2, dot, dot);
+                g.SmoothingMode = oldSmoothing;
+                cursor += dot + dotGap;
+                int remain = limit - cursor;
+                if (remain <= 0) break;
+                int tw = Theme.TextWidth(segment, Theme.Caption);
+                bool truncated = tw > remain;
+                var flags = TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.NoPadding
+                    | TextFormatFlags.SingleLine;
+                if (truncated) flags |= TextFormatFlags.EndEllipsis;
+                TextRenderer.DrawText(g, segment, Theme.Caption,
+                    new Rectangle(cursor, 0, Math.Min(tw + Theme.Px(2), remain), HeaderH),
+                    Invalid ? Theme.Danger : Theme.Ink2, flags);
+                cursor += Math.Min(tw, remain) + segGap;
+                if (truncated) break;
+            }
+        }
     }
 
     internal enum BtnKind { Secondary, Primary, Ghost }
@@ -831,14 +954,25 @@ namespace TfsExcelImporter
         private bool _invalid;
         private ComboBox _combo;
         private Chevron _chevron;
+        private SuffixIcon _suffix;
+        private Control _content;      // 主内容控件（TextBox/ComboBox），占位层据此判定显隐
+        private CueLabel _cue;         // 自绘占位提示：原生 EM_SETCUEBANNER 控制不了颜色/字号/对齐
         // 内容容器：整体内缩 2px 并按圆角 Region 裁剪——恰好让开聚焦态 2px 描边带，
         // 否则白底会切掉描边的内半圈，只剩外圈 AA 残边（视觉上就是一圈毛刺）。
         // 子控件（尤其被挤出宿主藏箭头的 ComboBox）再怎么越界，也只会被裁在描边圈以内。
         private Panel _box;
+        /// <summary>上一次 LayoutInner 时的宿主尺寸：尺寸没变就不用重摆子控件、更不用重建圆角 Region。</summary>
+        private Size _innerSize = new Size(-1, -1);
 
         /// <summary>宿主右侧留给自绘箭头的区域，同时也是点击展开下拉的热区。</summary>
         private int ArrowZone { get { return Theme.Px(26); } }
 
+        /// <summary>内容右侧的固定预留：组合框是箭头热区，文本框是尾部图标按钮（没有则 0）。</summary>
+        private int RightReserve
+        {
+            get { return _chevron != null ? ArrowZone : (_suffix != null ? Theme.Px(26) : 0); }
+        }
+
         /// <summary>内容左缘相对 _box 的缩进。TextBox 就摆在 Px(7)，组合框闭合态文字必须共用同一基准，
         /// 否则同一排的输入框文字会错开一条竖线。</summary>
         private static int TextInsetX { get { return Theme.Px(7); } }
@@ -896,16 +1030,56 @@ namespace TfsExcelImporter
                 _chevron.MouseDown += (s, e) => { if (e.Button == MouseButtons.Left) ToggleComboDropDown(); };
                 _box.Controls.Add(_chevron);
             }
+            _content = inner;
             inner.BackColor = Theme.Card;
             inner.Font = mono ? Theme.Mono : Theme.Body;
             inner.ForeColor = Theme.Ink;
             _box.Controls.Add(inner);
             inner.Enter += (s, e) => Invalidate();
             inner.Leave += (s, e) => Invalidate();
-            LayoutInner();
+            LayoutInner(true);
             return inner;
         }
 
+        /// <summary>文本框尾部图标按钮（如 Excel 字段的「浏览」）：点击执行回调，悬停着色提示可点。</summary>
+        public void AddSuffix(IconKind glyph, Action onClick)
+        {
+            if (_suffix != null) return;
+            _suffix = new SuffixIcon { Glyph = glyph };
+            _suffix.Click += (s, e) => { if (onClick != null) onClick(); };
+            _box.Controls.Add(_suffix);
+            LayoutInner(true);
+        }
+
+        /// <summary>忙等时独立禁用尾部按钮，不影响输入框本身的编辑。</summary>
+        public void SetSuffixEnabled(bool enabled)
+        {
+            if (_suffix != null) _suffix.Enabled = enabled;
+        }
+
+        /// <summary>
+        /// 自绘占位提示：比原生 EM_SETCUEBANNER 多出「浅灰、小字号、水平居中」三件事。
+        /// 鼠标经 HTTRANSPARENT 穿透到输入框，文字随内容输入即时显隐，与 Web placeholder 手感一致。
+        /// </summary>
+        public void SetCue(string text)
+        {
+            if (_cue == null)
+            {
+                _cue = new CueLabel();
+                _box.Controls.Add(_cue);
+            }
+            _cue.Text = text ?? "";
+            if (_content != null) _content.TextChanged += (s, e) => UpdateCueVisibility();
+            UpdateCueVisibility();
+            LayoutInner(true);
+        }
+
+        private void UpdateCueVisibility()
+        {
+            if (_cue != null && _content != null)
+                _cue.Visible = string.IsNullOrEmpty(_content.Text);
+        }
+
         protected override void OnSizeChanged(EventArgs e) { base.OnSizeChanged(e); LayoutInner(); }
 
         private void DrawComboItem(object sender, DrawItemEventArgs e)
@@ -953,14 +1127,19 @@ namespace TfsExcelImporter
                 | TextFormatFlags.SingleLine | TextFormatFlags.EndEllipsis);
         }
 
-        private void LayoutInner()
+        private void LayoutInner(bool force = false)
         {
             if (_box == null) return;   // 构造中途触发 OnSizeChanged 时容器可能还没建好
+            // 尺寸没变 → 子控件位置也不会变，直接跳过：这里一次要重摆 3~5 个真实子窗并重建 Region，
+            // 单次 3~4ms，重排里被反复调用的正是这种空转。
+            var hostSize = new Size(Width, Height);
+            if (!force && hostSize == _innerSize) return;
+            _innerSize = hostSize;
             _box.SetBounds(2, 2, Width - 4, Height - 4);
             SetBoxRegion();
             foreach (Control c in _box.Controls)
             {
-                if (c is Chevron) continue;
+                if (c is Chevron || c is SuffixIcon || c is CueLabel) continue;
                 var tb = c as TextBox;
                 var cb = c as ComboBox;
                 if (cb != null)
@@ -974,7 +1153,13 @@ namespace TfsExcelImporter
                 }
                 int natural = tb != null ? tb.PreferredHeight : Theme.Px(19);
                 int th = Math.Min(Math.Max(natural, Theme.Px(18)), _box.Height - Theme.Px(4));
-                c.SetBounds(Theme.Px(7), Math.Max(Theme.Px(2), (_box.Height - th) / 2), _box.Width - Theme.Px(14), th);
+                // Edit 自绘时把文字画在客户区上沿往下 Px(2) 处，而 PreferredHeight 底部还含着约
+                // Px(4) 的边框留白（BorderStyle=None 也不减）。直接按 PreferredHeight 居中，等于把
+                // 「上留白 2 + 文字 + 下留白 4」整体居中——文字就偏上 Px(2)，肉眼一眼能看出来。
+                // 把这段底部留白的一半补回来，文字才落在框内视觉中线上（Consolas / 雅黑都适用）。
+                int textTopFix = tb != null ? Theme.Px(2) : 0;
+                c.SetBounds(Theme.Px(7), Math.Max(Theme.Px(2), (_box.Height - th) / 2) + textTopFix,
+                    _box.Width - Theme.Px(14) - RightReserve, th);
             }
             if (_chevron != null)
             {
@@ -982,6 +1167,21 @@ namespace TfsExcelImporter
                 _chevron.SetBounds(_box.Width - Theme.Px(7) - size, Theme.Px(2), size, _box.Height - Theme.Px(4));
                 _chevron.BringToFront();   // 后加的兄弟控件在底层，必须提到组合框上方才看得见
             }
+            if (_suffix != null)
+            {
+                int size = Theme.Px(16);
+                _suffix.SetBounds(_box.Width - Theme.Px(8) - size, Theme.Px(2), size, _box.Height - Theme.Px(4));
+            }
+            if (_cue != null)
+            {
+                // 与内容文字同一缩进基准，宽度让开尾部箭头/图标区；文字左对齐（不再居中）。
+                // 起点就用 TextInsetX：实测（150% 截图）空态占位与已填内容的第一个墨迹列
+                // 相对左边框都在 +13px，多让或让少都会在「敲字瞬间」看到文字横跳。
+                _cue.SetBounds(TextInsetX, Theme.Px(2),
+                    Math.Max(Theme.Px(24), _box.Width - TextInsetX - Theme.Px(7) - RightReserve),
+                    _box.Height - Theme.Px(4));
+                _cue.BringToFront();
+            }
             Invalidate();
         }
 
@@ -1018,6 +1218,64 @@ namespace TfsExcelImporter
             }
         }
 
+        /// <summary>输入框尾部图标按钮：白底上悬停变主色，点击交给外部回调。</summary>
+        private sealed class SuffixIcon : Control
+        {
+            public IconKind Glyph = IconKind.None;
+            private bool _hover;
+
+            public SuffixIcon()
+            {
+                SetStyle(ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint
+                    | ControlStyles.OptimizedDoubleBuffer | ControlStyles.ResizeRedraw
+                    | ControlStyles.SupportsTransparentBackColor, true);
+                BackColor = Theme.Card;
+                Cursor = Cursors.Hand;
+                TabStop = false;
+            }
+
+            protected override void OnMouseEnter(EventArgs e) { base.OnMouseEnter(e); _hover = true; Invalidate(); }
+            protected override void OnMouseLeave(EventArgs e) { base.OnMouseLeave(e); _hover = false; Invalidate(); }
+            protected override void OnEnabledChanged(EventArgs e) { base.OnEnabledChanged(e); Invalidate(); }
+
+            protected override void OnPaint(PaintEventArgs e)
+            {
+                int size = Theme.Px(16);
+                Icons.Draw(e.Graphics, Glyph,
+                    new Rectangle((Width - size) / 2, (Height - size) / 2, size, size),
+                    _hover && Enabled ? Theme.Primary : Theme.Ink2);
+            }
+        }
+
+        /// <summary>占位提示层：小一号字号、置灰、左对齐并贴住真实文字的左缘；鼠标事件穿透，不挡输入框聚焦与编辑。</summary>
+        private sealed class CueLabel : Control
+        {
+            public CueLabel()
+            {
+                SetStyle(ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint
+                    | ControlStyles.OptimizedDoubleBuffer | ControlStyles.ResizeRedraw, true);
+                BackColor = Theme.Card;
+                TabStop = false;
+            }
+
+            protected override void WndProc(ref Message m)
+            {
+                const int WM_NCHITTEST = 0x84;
+                if (m.Msg == WM_NCHITTEST) { m.Result = (IntPtr)(-1); return; }   // HTTRANSPARENT：点击穿透
+                base.WndProc(ref m);
+            }
+
+            protected override void OnPaint(PaintEventArgs e)
+            {
+                // 左对齐：占位文字必须从真实文字的起点起头，用户一敲字两个位置才不跳动。
+                // NoPadding 去掉 DrawText 自带的 2px 文字边距，起点完全由外层给的 x 决定。
+                TextRenderer.DrawText(e.Graphics, Text, Theme.Caption,
+                    new Rectangle(0, 0, Width, Height), Theme.Ink3,
+                    TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.NoPadding
+                    | TextFormatFlags.SingleLine | TextFormatFlags.EndEllipsis);
+            }
+        }
+
         protected override void OnMouseDown(MouseEventArgs e)
         {
             base.OnMouseDown(e);