feat: 任务模型物理合并，发布+回收并为单任务双阶段

- tasks 新增 recovery_enabled/recovery_due_at/recovery_instructions/recovery_example_images，回收挂自己名下（先发布后交截图），不再置 complete
- 存量 screenshot_collect 迁移并入父任务后删除（mysql/0020 含 DELETE，生产执行前务必备份）
- 新 action task_enable_recovery：ghost 面板一键开通回收，截止默认=发布截止
- 企微催办双阶段（待发布/截图待提交）；超期自动释放仅发布阶段
- admin 删 groupTaskMasters 聚合改单卡双面板；portal 详情页回收截图区块+批次回收进度
- 测试 309 全绿 + Playwright E2E 20/20

tests/wecom-group-push.test.mjs

@@ -54,17 +54,18 @@ test("buildTaskGroupPushMessage composes text and link with claim url", () => {
   assert.match(message.link.desc, /品牌A · 3 份 · 截止 2026-09-01/);
 });
 
-test("buildTaskGroupPushMessage marks video and screenshot tasks", () => {
+test("buildTaskGroupPushMessage marks video tasks (单模型下不再有截图任务文案)", () => {
   const video = buildTaskGroupPushMessage(
     { ...baseTask, content_format: "video" },
     "https://portal.example.com",
   );
   assert.match(video.text, /形式：视频/);
-  const screenshot = buildTaskGroupPushMessage(
-    { ...baseTask, task_type: "screenshot_collect" },
+  const imageText = buildTaskGroupPushMessage(
+    baseTask,
     "https://portal.example.com",
   );
-  assert.match(screenshot.text, /形式：截图回收/);
+  assert.match(imageText.text, /形式：图文/);
+  assert.doesNotMatch(imageText.text, /截图回收/);
 });
 
 test("buildTaskGroupPushMessage drops link when share_token missing", () => {