Retire ACP/Hermes/OpenCode surfaces and rename hermes_tools to
mnote_agent_tools so Page AI stays on Pi Lab only. Add Chrome vault
extension + extension token route, pre-release purge design, and soft-retire
legacy smokes for the small-group production cut.
- expose Pi Rust built-in tools by permission mode instead of replacing them with MNote file tools
- update Pi Lab smoke coverage for native ls/read/bash usage
- document the overreplacement regression and verification evidence