chore: sync agent docs, gitignore, and VS Code tasks (#432)

- Migrate release-manager from gh CLI to GitHub MCP tool usage
- Add workspace hygiene and source-of-truth audit rules
- Add pre-PR local quality gate and no-CI-first-failures policy
- Update testing-manager with enhanced validation workflow
- Add scheduler lock files to .gitignore
- Add E2E test task configurations to VS Code tasks

.gitignore

@@ -86,4 +86,5 @@ doku/
 doku/memory_notes.md
 doku/report.md
 plan/
-.copilot-tracking
+.copilot-tracking/
+.playwright-cli/