fix(task): fix manual retry button visibility and validation

- Only show the manual retry button for failed tasks (status === "failed") on the frontend.
- Remove the maximum retry limit validation for manual retries in the task executor.
- Remove obsolete test cases verifying maximum retry limit for manual retries.

frontend/components/common/admin/task-executions.tsx

@@ -379,7 +379,7 @@ export function TaskExecutionsManager() {
               {detailLoading ? <Spinner className="size-4" /> : <RefreshCw className="size-4" />}
               刷新详情
             </Button>
-            {selectedExecution && selectedExecution.status !== "pending" && selectedExecution.status !== "running" && selectedExecution.retryable && selectedExecution.retry_count < selectedExecution.max_retry && (
+            {selectedExecution && selectedExecution.status === "failed" && selectedExecution.retryable && (
               <Button onClick={handleRetryExecution} disabled={retrying}>
                 {retrying ? <Spinner className="size-4" /> : <RotateCcw className="size-4" />}
                 重试任务

internal/apps/admin/task/routers_test.go

@@ -491,32 +491,3 @@ func TestRetryTask(t *testing.T) {
 		assert.Equal(t, http.StatusBadRequest, w.Code)
 	})
 }
-
-func TestRetryTaskMaxRetryExceeded(t *testing.T) {
-	cleanup := setupTaskTestEnvironment(t)
-	defer cleanup()
-
-	adminUser := &model.User{ID: 1001, Username: "admin", IsAdmin: true}
-	router := setupTestRouter(adminUser)
-	ctx := context.Background()
-
-	execution := &model.TaskExecution{
-		TaskID:      "retry_max_api_001",
-		TaskType:    "system:cleanup",
-		TaskName:    "系统垃圾清理",
-		Status:      model.TaskExecutionStatusFailed,
-		Retryable:   true,
-		MaxRetry:    1,
-		RetryCount:  1,
-		TriggeredBy: "retry",
-	}
-	err := model.CreateTaskExecution(ctx, execution)
-	require.NoError(t, err)
-
-	url := fmt.Sprintf("/api/v1/admin/tasks/executions/%d/retry", execution.ID)
-	req, _ := http.NewRequest("POST", url, nil)
-	w := httptest.NewRecorder()
-	router.ServeHTTP(w, req)
-
-	assert.Equal(t, http.StatusBadRequest, w.Code)
-}

internal/task/executor.go

@@ -163,10 +163,6 @@ func RetryTask(ctx context.Context, id uint64) (string, error) {
 		return "", errors.New(errTaskNotRetryable)
 	}
 
-	if execution.RetryCount >= execution.MaxRetry {
-		return "", fmt.Errorf(errTaskMaxRetryExceeded, execution.MaxRetry)
-	}
-
 	// 生成新的 TaskID
 	newTaskID := generateRetryTaskID(execution.TaskID, execution.RetryCount+1)
 

internal/task/executor_test.go

@@ -339,29 +339,6 @@ func TestRetryTaskNotRetryable(t *testing.T) {
 	assert.Contains(t, err.Error(), "不支持重试")
 }
 
-func TestRetryTaskMaxRetryExceeded(t *testing.T) {
-	cleanup := setupTest(t)
-	defer cleanup()
-	ctx := context.Background()
-
-	execution := &model.TaskExecution{
-		TaskID:      "retry_max_001",
-		TaskType:    testTaskType,
-		TaskName:    "测试任务",
-		Status:      model.TaskExecutionStatusFailed,
-		Retryable:   true,
-		MaxRetry:    2,
-		RetryCount:  2,
-		TriggeredBy: "retry",
-	}
-	err := model.CreateTaskExecution(ctx, execution)
-	require.NoError(t, err)
-
-	_, err = RetryTask(ctx, execution.ID)
-	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "已达到最大重试次数")
-}
-
 func TestRetryTaskNonExistent(t *testing.T) {
 	cleanup := setupTest(t)
 	defer cleanup()