Tagvico AI v2.0.1

Security\n\n- Prevent unauthenticated replacement of configuration and the local admin account through POST /setup after setup has completed.\n\n## Documentation\n\n- Pin v2 installation examples to the immutable 2.0.1 image.\n- Clarify one-time remote setup, the 409 recovery path, and exact rollback steps.\n\n## Validation\n\n- CI quality gate passed.\n- Node 22: 84 unit tests, type/lint/branding/EJS/browser checks, and versioned docs build passed.