feat: unify status feedback for copy, save and cancel actions

Route the copy-to-clipboard and save-to-disk pipelines through
emitOperationStatus so they show the same running/success/error stages
as the upload, save-remote and summary flows, and surface a short
"已取消" status when a capture is cancelled. This gives every capture
action a consistent HUD experience.

app.go

@@ -320,17 +320,32 @@ func (a *App) runUploadPipeline(provider domain.OSSProvider, pngBytes []byte) er
 func (a *App) runCopyImagePipeline(pngBytes []byte) error {
 	svc := &application.CaptureActionsService{
 		Clipboard: a.clip,
-		Notifier:  &runtimeNotifier{ctx: a.ctx},
 	}
-	return svc.CopyImage(a.ctx, pngBytes)
+	a.emitOperationStatus("copy", "复制中", "正在把截图复制到剪贴板", "running")
+	if err := svc.CopyImage(a.ctx, pngBytes); err != nil {
+		a.emitOperationStatus("copy", "复制失败", err.Error(), "error")
+		wruntime.EventsEmit(a.ctx, "upload:failure", err.Error())
+		return err
+	}
+	a.emitOperationStatus("copy", "复制完成", "截图已复制到剪贴板", "success")
+	wruntime.EventsEmit(a.ctx, "upload:success", "image copied to clipboard")
+	return nil
 }
 
 func (a *App) runSaveImagePipeline(pngBytes []byte, dir string) (string, error) {
 	svc := &application.CaptureActionsService{
 		Clipboard: a.clip,
-		Notifier:  &runtimeNotifier{ctx: a.ctx},
 	}
-	return svc.SaveImage(a.ctx, pngBytes, dir)
+	a.emitOperationStatus("save", "保存中", "正在保存截图到本地", "running")
+	path, err := svc.SaveImage(a.ctx, pngBytes, dir)
+	if err != nil {
+		a.emitOperationStatus("save", "保存失败", err.Error(), "error")
+		wruntime.EventsEmit(a.ctx, "upload:failure", err.Error())
+		return "", err
+	}
+	a.emitOperationStatus("save", "保存完成", path, "success")
+	wruntime.EventsEmit(a.ctx, "upload:success", path)
+	return path, nil
 }
 
 // runSaveRemotePipeline uploads the captured PNG to the configured SSH host
@@ -939,6 +954,7 @@ func (a *App) CancelRegion() {
 	a.pendingMu.Unlock()
 	a.capturing.Store(false)
 	a.dismissOverlay()
+	a.emitOperationStatus("capture", "已取消", "本次截图已取消", "success")
 }
 
 // CancelNativeRegion releases native-overlay state without touching the
@@ -949,6 +965,7 @@ func (a *App) CancelNativeRegion() {
 	a.pendingMu.Unlock()
 	a.capturing.Store(false)
 	hideDockIcon()
+	a.emitOperationStatus("capture", "已取消", "本次截图已取消", "success")
 }
 
 // ShowWindow brings the main window back to the foreground in its normal