Exposes agent hooks over WebSocket (hooks.list/create/update/delete/
toggle/test/history) behind existing auth layer. Additions:
- Gateway wiring: buildHookHandlers() factory reused by dispatcher and
hooks.test runner, so UI test panel exercises production code paths
- GetByID tenant-scope guard: non-master callers only see own tenant +
global rows (matches List() behavior on both PG and SQLite)
- i18n keys + catalogs (en/vi/zh) for hooks error messages
- Protocol method constants for hooks.* and config.defaults
