fix: 修复长时间运行后的卡死问题

MainForm.cs

@@ -412,7 +412,7 @@ namespace TimerApp
         {
             if (InvokeRequired)
             {
-                Invoke(new Action<object?, EventArgs>(Monitor_StateChanged), sender, e);
+                BeginInvoke(new Action<object?, EventArgs>(Monitor_StateChanged), sender, e);
                 return;
             }
             UpdateStatusUI();
@@ -461,19 +461,25 @@ namespace TimerApp
         {
             if (InvokeRequired)
             {
-                Invoke(new Action<object?, TimeSpan>(Monitor_WorkProgressChanged), sender, remaining);
+                BeginInvoke(new Action<object?, TimeSpan>(Monitor_WorkProgressChanged), sender, remaining);
                 return;
             }
             lblTimeLeft.Text = $"{remaining.Minutes:D2}:{remaining.Seconds:D2}";
 
             // Update tray tooltip
+            string newText;
             if (remaining.TotalMinutes < 1)
             {
-                notifyIcon1.Text = $"即将休息: {remaining.Seconds}秒";
+                newText = $"即将休息: {remaining.Seconds}秒";
             }
             else
             {
-                notifyIcon1.Text = $"工作中: 剩余 {remaining.Minutes} 分钟";
+                newText = $"工作中: 剩余 {remaining.Minutes} 分钟";
+            }
+
+            if (notifyIcon1.Text != newText)
+            {
+                notifyIcon1.Text = newText;
             }
         }
 
@@ -481,7 +487,7 @@ namespace TimerApp
         {
             if (InvokeRequired)
             {
-                Invoke(new Action<object?, EventArgs>(Monitor_RestStarted), sender, e);
+                BeginInvoke(new Action<object?, EventArgs>(Monitor_RestStarted), sender, e);
                 return;
             }
 
@@ -503,6 +509,12 @@ namespace TimerApp
 
         private void Monitor_RestProgressChanged(object? sender, TimeSpan remaining)
         {
+            if (InvokeRequired)
+            {
+                BeginInvoke(new Action<object?, TimeSpan>(Monitor_RestProgressChanged), sender, remaining);
+                return;
+            }
+
             if (_restForm != null && !_restForm.IsDisposed && _restForm.Visible)
             {
                 _restForm.UpdateTime(remaining);
@@ -513,7 +525,7 @@ namespace TimerApp
         {
             if (InvokeRequired)
             {
-                Invoke(new Action<object?, EventArgs>(Monitor_RestEnded), sender, e);
+                BeginInvoke(new Action<object?, EventArgs>(Monitor_RestEnded), sender, e);
                 return;
             }
 
@@ -568,9 +580,15 @@ namespace TimerApp
 
         private void ShowForm()
         {
+            if (this.IsDisposed) return;
+            
             this.Show();
-            this.WindowState = FormWindowState.Normal;
+            if (this.WindowState == FormWindowState.Minimized)
+            {
+                this.WindowState = FormWindowState.Normal;
+            }
             this.Activate();
+            this.BringToFront();
         }
 
         public void ActivateFromExternal()