feat: implement LLM table translation service with searchable datasource dropdown, i18n, sidebar, and RBAC

- Add backend plugin modules: preview, executor, orchestrator, events, sql_generator, superset_executor, dictionary, scheduler, metrics
- Add API routes for translate jobs, runs, dictionaries, preview, schedule, metrics, corrections
- Add ORM models (12 tables) and Pydantic schemas (15 DTOs)
- Register translate router in app.py with RBAC permission guards
- Add frontend pages: job list, job config, dictionary list/editor, history
- Add 7 reusable Svelte 5 components: Preview, RunProgress, RunResult, TermCorrection, BulkCorrection, ScheduleConfig, MetricsDashboard
- Add searchable datasource dropdown with Superset API integration
- Add i18n (en/ru) with ~300 keys across common, config, jobs, dictionaries, preview namespaces
- Add Translation sidebar category with Jobs/Dictionaries/History sub-items
- Hide health monitor error toast via suppressToast API option
- Add 69 backend tests and 44 frontend test files
- Fix: SupersetClient env resolution (string -> Environment object)
- Fix: Dataset detail API returns proper database dict
- Fix: Database dialect extraction fallback when metadata incomplete

backend/src/app.py

@@ -53,6 +53,7 @@ from .api.routes import (
     profile,
     health,
     dataset_review,
+    translate,
 )
 from .api import auth
 
@@ -271,6 +272,7 @@ app.include_router(clean_release_v2.router)
 app.include_router(profile.router)
 app.include_router(dataset_review.router)
 app.include_router(health.router)
+app.include_router(translate.router)
 # [/DEF:API_Routes:Block]