docs: v0.3.0 发布记录与发布前 E2E 回归门禁报告

- 新建常设「发布记录」页（挂开发文档导航），首条 v0.3.0 M3 社区
- 30 号报告：M2 11/11 + M3 14/14 同环境各连跑 3 轮零 flake、契约偏差 0；
  附契约向后兼容结构化比对（removed/changed 均 NONE）与共享代码面回归分析
- 记录首次发布的一次性操作：api main 孤儿历史重建（方案 A）、flutter 快进推法改进

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

mkdocs.yml

@@ -8,6 +8,7 @@ nav:
       - Git 工作流规范: development/git-workflow.md
       - 功能完成清单: development/feature-checklist.md
       - 真机验证清单: development/device-verification.md
+      - 发布记录: development/releases.md
       - CI Runner 部署手册: development/ci-runner-setup.md
       - 第一迭代:
           - 进展看板: development/iterations/iteration-1/index.md
@@ -94,6 +95,7 @@ nav:
           - 27 第三波收口: development/iterations/iteration-3/27-wave3-closure.md
           - 28 E2E 烟囱收官: development/iterations/iteration-3/28-e2e-smoke-report.md
           - 29 M3 收官总结: development/iterations/iteration-3/29-m3-summary.md
+          - 30 发布 E2E 回归: development/iterations/iteration-3/30-release-e2e-regression.md
   - API:
       - 契约说明: api/index.md
   - 架构: