- MemoriesTab: auto-run health check on mount + poll every 30s (was manual-only).
- page: add enable/disable memory toggle (role=switch) via useMemorySettings.save({ enabled }).
- MemoryEngineStatus: show "npm install sqlite-vec" hint when vector store backend is "none".
- i18n: memory.memoryEnabled + memory.engine.vectorStoreInstallHint (en + pt-BR).