Preserve the validated local resume and bounded repair handoff

Why: Continue the authorized CI repair with reconciled task identity.

Evidence: The original LOCAL_READY receipt is imported through make task-resume.

Impact: Task metadata only; final delivery still requires synchronization and CI.

Refs: PR #651

.task/feature-conversation-handoff.md

@@ -163,3 +163,45 @@
 - Backend 已登记任务工作区已保留并移至 `/home/weichen/projects/Agent-System-Backend-wt-fix-ci-pg-flaky-tests`，修复 Git 与唯一已初始化子模块的路径元数据；Dev 工作树的未跟踪嵌套工作区阻塞已消除。
 - 启动检查原始 SELF 收据：`/tmp/pr651-resume-20261020-a1.json`（SHARED_WORKSPACE_BUSY）、`/tmp/pr651-resume-20261020-a2.json`（任务卡已归档，拒绝 LOCAL_READY）；不宣称通过。恢复活动卡后重新检查。
 - GATE 重新只读核验：PR #651 head `19566bfde79313dfaea31ff6f5ca918f820c1606` 仍开放；run 4404 的 test/svc-realcombo success，test-pg failure；日志 `/tmp/pr651-job7141.log`。目标 main 当前 `f1866dc3bb4537ac6446fdd26e696cb636b543ef`；#648 持有交付窗口，本任务先局部排障。
+
+<!-- Local receipt: SELF. Digests detect corruption; they do not authenticate a reviewer or CI. -->
+```json
+{
+  "summary_schema": 1,
+  "source": "SELF",
+  "timestamp": "2026-10-20T08:46:38.272183+00:00",
+  "command": "make precheck",
+  "exit_code": 0,
+  "cwd": "/home/weichen/projects/Agent-System-Dev-wt-feature-conversation-handoff",
+  "before_head": "f9884db84b7fb5752d50b641f09adb75303e327c",
+  "after_head": "f9884db84b7fb5752d50b641f09adb75303e327c",
+  "branch": "feature/conversation-handoff",
+  "target_branch": "main",
+  "target_head": "adbef2f49c6c252a09449496afbdb6685201993b",
+  "root_target": "main",
+  "immediate_target": "main",
+  "before_tracked_diff_sha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  "after_tracked_diff_sha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  "output_tail": [
+    "make[1]: Entering directory '/home/weichen/projects/Agent-System-Dev-wt-feature-conversation-handoff'",
+    "[repo]   branch=feature/conversation-handoff head=f9884db84b",
+    "[remote] origin/main=adbef2f49c ahead=6 behind=26",
+    "[tree]   clean submodules_drift=0 uninit=0",
+    "[worktrees] linked=6",
+    "[initiatives] local cards (not authoritative): none",
+    "[hooks]   core.hooksPath=scripts/hooks（pre-commit/post-merge 实际接线）",
+    "[facts]   policy/facts.md 6 条事实均在有效期内",
+    "[required-reading] core/baseline.md, workflows/delivery.md §1, policy/delivery.md",
+    "[target] adbef2f49c6c252a09449496afbdb6685201993b（observed; task initial baseline is reported separately）",
+    "[task-state] registered=/home/weichen/projects/Agent-System-Dev-wt-feature-conversation-handoff initial_base=f97917032d143188bc7faf665aff612d9814af4e",
+    "[verdict] LOCAL_READY — existing task may continue authorized local work; final delivery still requires latest-target sync and checks",
+    "make[1]: Leaving directory '/home/weichen/projects/Agent-System-Dev-wt-feature-conversation-handoff'"
+  ],
+  "output_sha256": "be0eda106b0ed68d8f108a607b83c5231d1c34c744675a83995638fa5e39aa43",
+  "receipt_sha256": "12bb48774c59da7635b3b0cf1ef81465b5fe29475baaf880c72a1a82a0649f46",
+  "receipt_path": "/home/weichen/.cache/agent-system-dev/evidence/12bb48774c59da7635b3b0cf1ef81465b5fe29475baaf880c72a1a82a0649f46.json"
+}
+```
+
+- 局部恢复已通过并导入：`/tmp/pr651-resume-20261020-a6.json`（LOCAL_READY，SELF）；正式交付需新鲜同步与固定 HEAD CI。
+- 新 repair 单元：`ci-pg-async-completion-r2`；固定 Backend base `e927694818f3c0b79ec663d70ab2aa9d47d8fd8f`；工作包 `/tmp/pr651-repair-unit-r2.json`；收据目标 `/tmp/pr651-repair-r2.json`；运行中，尚无成功产物。