[moz] feat(prompt): L0~L2 prompt improvements

- L0 wiki-rule: 扩充检索路径（practices/concepts/docs/design/）+ 检索方式（index→summary→grep→full）
- L1 SOUL.md: 同步测试 + PR 审查（代码改动检查设计文档+测试脚本，PR/CI/CD 三重把关）
- L1 AGENTS.md: 新增测试规范段（生产隔离/残留清理/测试开发分离）
- L2 prompt_composer: 新增 DeliveryChecklistSection（executor/mail/toolchain handler 注册）
- 456 passed, 0 failed

src/daemon/mail_handler.py

@@ -9,7 +9,7 @@ import logging
 from pathlib import Path
 
 from src.daemon.base_task_handler import BaseTaskHandler, VerifyResult
-from src.daemon.prompt_composer import PromptComposer, PromptContext, GiteaConventionSection, WikiGuideSection
+from src.daemon.prompt_composer import PromptComposer, PromptContext, GiteaConventionSection, WikiGuideSection, DeliveryChecklistSection
 from src.blackboard.db import get_connection
 
 logger = logging.getLogger("moziplus-v2.handler.mail")
@@ -36,7 +36,7 @@ class MailHandler(BaseTaskHandler):
         return composer.compose(context)
 
     def get_sections(self) -> list:
-        return [MailContextSection(), MailApiSection(), MailConstraintsSection(), GiteaConventionSection(), WikiGuideSection()]
+        return [MailContextSection(), MailApiSection(), MailConstraintsSection(), GiteaConventionSection(), WikiGuideSection(), DeliveryChecklistSection()]
 
     def verify_completion(self, task_id: str, db_path: Path) -> VerifyResult:
         """Mail 完成验证：区分 inform/request。