fix: critical QA findings — dead code and prop mismatch

1. Remove get_config_manager() call from translate_run_websocket
   (@app.websocket /ws/translate/run/{run_id}) — was not imported
   and unused. Also remove unused from sqlalchemy.orm import Session.
2. Fix prop name mismatch: showBulkReplace -> showPageBulkReplace
   in RunTabContent. Use () for reactive two-way binding.
3. Add ('DRAFT') for status prop in RunTabContent.

backend/src/app.py

@@ -640,10 +640,8 @@ async def translate_run_websocket(websocket: WebSocket, run_id: str):
     await websocket.accept()
     logger.reason("Accepted translate run WebSocket", extra={"run_id": run_id})
     try:
-        config_manager = get_config_manager()
         while True:
             try:
-                from sqlalchemy.orm import Session
                 from .core.database import SessionLocal
                 from .plugins.translate.orchestrator_aggregator import TranslationResultAggregator
                 from .core.event_log import EventLog