feat: reorganize project task planning UI

backend/internal/logic/projects/service.go

@@ -54,14 +54,16 @@ type InboxMessage struct {
 }
 
 type WorkTask struct {
-	ID        string `json:"id"`
-	Title     string `json:"title"`
-	Summary   string `json:"summary"`
-	Completed bool   `json:"completed"`
-	Owner     string `json:"owner"`
-	Due       string `json:"due"`
-	CreatedAt string `json:"createdAt"`
-	Tag       string `json:"tag"`
+	ID          string `json:"id"`
+	Title       string `json:"title"`
+	Summary     string `json:"summary"`
+	Completed   bool   `json:"completed"`
+	Owner       string `json:"owner"`
+	Due         string `json:"due"`
+	CreatedAt   string `json:"createdAt"`
+	CompletedAt string `json:"completedAt"`
+	Duration    string `json:"duration"`
+	Tag         string `json:"tag"`
 }
 
 type AISessionItem struct {
@@ -550,15 +552,24 @@ func (s *Service) workspaceTasks(projectID uint) ([]WorkTask, error) {
 		if err != nil {
 			return nil, err
 		}
+		completed := task.Status == "done"
+		completedAt := ""
+		duration := ""
+		if completed {
+			completedAt = displayTime(task.UpdatedAt)
+			duration = displayDuration(task.CreatedAt, task.UpdatedAt)
+		}
 		items = append(items, WorkTask{
-			ID:        fmt.Sprint(task.ID),
-			Title:     task.Title,
-			Summary:   task.Description,
-			Completed: task.Status == "done",
-			Owner:     owner,
-			Due:       displayOptionalTime(task.DueAt),
-			CreatedAt: displayTime(task.CreatedAt),
-			Tag:       tagNames[task.ID],
+			ID:          fmt.Sprint(task.ID),
+			Title:       task.Title,
+			Summary:     task.Description,
+			Completed:   completed,
+			Owner:       owner,
+			Due:         displayOptionalTime(task.DueAt),
+			CreatedAt:   displayTime(task.CreatedAt),
+			CompletedAt: completedAt,
+			Duration:    duration,
+			Tag:         tagNames[task.ID],
 		})
 	}
 	return items, nil
@@ -740,6 +751,26 @@ func displayOptionalTime(value *time.Time) string {
 	return displayTime(*value)
 }
 
+func displayDuration(start time.Time, end time.Time) string {
+	if start.IsZero() || end.IsZero() || end.Before(start) {
+		return ""
+	}
+	duration := end.Sub(start)
+	days := int(duration.Hours()) / 24
+	if days > 0 {
+		return fmt.Sprintf("%d 天", days)
+	}
+	hours := int(duration.Hours())
+	if hours > 0 {
+		return fmt.Sprintf("%d 小时", hours)
+	}
+	minutes := int(duration.Minutes())
+	if minutes > 0 {
+		return fmt.Sprintf("%d 分钟", minutes)
+	}
+	return "1 分钟内"
+}
+
 func sourceDisplayName(source models.SenlinAgentSource) string {
 	switch source.Kind {
 	case "file":