feat(translate): complete Phase 10-11 — full spec 028 closure (T075-T134)

Phase 10 closure:
- T075: NotificationService wiring for scheduled-run failures
- T077: Semantic audit via axiom MCP (0 warnings)
- T078: Quickstart validation — all 165+280 tests pass

Phase 11 completion:
- T083-T086: Multi-language models/schemas/Alembic migration
- T087-T090: Auto-detect source language (BCP-47) + tests
- T091-T095: Multilingual dictionaries with language-pair filtering
- T096-T108: Multi-language job config → preview → execution pipeline
- T109-T118: Inline correction + BulkReplaceModal + CorrectionCell + tests
- T119-T122: Per-language history and MetricSnapshot
- T123-T134: Context-aware corrections (Jaccard similarity, priority flagging, context_data)

New files: Alembic migration, test_scheduler, test_inline_correction,
BulkReplaceModal, vitest for CorrectionCell + BulkReplaceModal

Total: 134/134 tasks complete. Backend 165p, Frontend 280p.

backend/src/api/routes/translate/_correction_routes.py

@@ -47,6 +47,7 @@ async def submit_correction(
             origin_user_id=current_user.username,
             context_data=payload.context_data,
             usage_notes=payload.usage_notes,
+            keep_context=payload.keep_context,
         )
         return result
     except ValueError as e: