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

app/api/partner-image/route.ts

@@ -75,9 +75,11 @@ async function handleGet(request: Request) {
                     c.video_assets,
                     d.result_screenshot_key,
                     d.publish_screenshot_key,
-                    d.screenshot_key
+                    d.screenshot_key,
+                    t.recovery_example_images
              FROM distributions d
              JOIN contents c ON c.id = d.content_id
+             JOIN tasks t ON t.id = d.task_id
              JOIN delegation_bundles b ON b.id = d.delegation_bundle_id
              WHERE d.id = ?
                AND b.share_token = ?
@@ -90,6 +92,7 @@ async function handleGet(request: Request) {
             result_screenshot_key: string | null;
             publish_screenshot_key: string | null;
             screenshot_key: string | null;
+            recovery_example_images: string;
           }>()
       : await getRawDb()
           .prepare(
@@ -97,7 +100,8 @@ async function handleGet(request: Request) {
                     c.video_assets,
                     d.result_screenshot_key,
                     d.publish_screenshot_key,
-                    d.screenshot_key
+                    d.screenshot_key,
+                    t.recovery_example_images
              FROM distributions d
              JOIN contents c ON c.id = d.content_id
              JOIN claims cl ON cl.id = d.claim_id
@@ -114,6 +118,7 @@ async function handleGet(request: Request) {
             result_screenshot_key: string | null;
             publish_screenshot_key: string | null;
             screenshot_key: string | null;
+            recovery_example_images: string;
           }>();
     const asset =
       imageKind === "result"
@@ -125,6 +130,10 @@ async function handleGet(request: Request) {
               ],
             }
           : undefined
+        : imageKind === "task-example"
+          ? row
+            ? findAsset(row.recovery_example_images, imageIndex, ["task-assets/"])
+            : undefined
         : imageKind === "publish"
           ? row?.publish_screenshot_key?.startsWith("publish-evidence/")
             ? { index: 1, key: row.publish_screenshot_key }