docs(asl): Upgrade Tool 3 architecture from Fan-out to Scatter+Aggregator (v2.0)

Architecture transformation:
- Replace Fan-out (Manager->Child->Last Child Wins) with Scatter+Aggregator pattern
- API layer directly dispatches N independent jobs (no Manager)
- Worker only writes its own Result row, never touches Task table (zero row-lock)
- Aggregator polls groupBy for completion + zombie cleanup (replaces Sweeper)
- Reduce red lines from 13 to 9, eliminate distributed complexity

Documents updated (10 files):
- 08-Tool3 main architecture doc: v2.0 rewrite (schema, Task 2.3/2.4, red lines, risks)
- 08d-Code patterns: rewrite sections 4.1-4.6 (API dispatch, SingleWorker, Aggregator)
- 08a-M1 sprint: rewrite M1-3 core (Worker+Aggregator), red lines, acceptance criteria
- 08b-M2 sprint: simplify SSE (NOTIFY/LISTEN downgraded to P2 optional)
- 08c-M3 sprint: milestone table wording update
- New: Scatter+Polling Aggregator pattern guide v1.1 (Level 2 cookbook)
- New: V2.0 architecture deep review and gap-fix report
- Updated: ASL module status, system status, capability layer index

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/02-通用能力层/Postgres-Only异步任务处理指南.md

@@ -721,6 +721,7 @@ this.boss.on('error', (err) => {
 | **DC Tool C** | `parseExcelWorker.ts` | `useSessionStatus.ts` | 本指南基础 |
 | **ASL 智能文献** | `screeningWorker.ts` | `useScreeningTask.ts` | [ASL模块状态](../03-业务模块/ASL-AI智能文献/00-模块当前状态与开发指南.md) |
 | **DC Tool B** | `extractionWorker.ts` | - | [DC模块状态](../03-业务模块/DC-数据清洗整理/00-模块当前状态与开发指南.md) |
+| **🆕ASL 工具 3** | 散装派发 + Aggregator | `useTaskStatus.ts` | [散装派发与轮询收口指南](./散装派发与轮询收口任务模式指南.md)（Level 2 批量模式） |
 
 ---