feat(data-entry): Bulk Receipt Upload cu Mobile UX Android Nativ

## Funcționalități Principale

### Bulk Upload & Processing
- Drag & drop pentru upload bonuri multiple oriunde pe pagină
- Batch processing cu job queue și worker pool
- Real-time updates via SSE (Server-Sent Events) cu fallback polling
- Duplicate detection via SHA-256 file hash
- Auto-retry pentru job-uri failed
- Cancel individual jobs sau batch complet

### Mobile UX - Android Native Style
- Top bar fixă cu hamburger, titlu centrat, acțiuni (search/filter)
- Bottom navigation cu 4 tab-uri (Bonuri, Upload, Rapoarte, Setări)
- FAB (Floating Action Button) cu hide/show on scroll
- Filter chips orizontal scrollabile
- Selecție multiplă prin long-press (500ms)
- Select All + Bulk Delete cu confirmare
- Layout Android pentru Create/Edit/View bon (Gmail compose style)

### Bug Fixes
- Refresh individual via SSE în loc de refresh total pagină
- Bonurile cu eroare OCR rămân vizibile pentru editare manuală
- Afișare nume fișier original pentru toate bonurile
- Upload stabil pe mobil (fix race condition File API)
- Păstrare ordine bonuri la refresh (nu se reordonează)

### Backend
- SSE endpoint pentru status updates real-time
- Bulk delete endpoint cu partial success
- Auto-cleanup bonuri failed după 7 zile
- Batch model cu tracking complet

### Testing
- E2E tests cu Playwright
- Unit tests pentru bulk upload, auto-create, cleanup

## Commits Squashed: 43 user stories (US-001 → US-043)
## Branch: ralph/bulk-receipt-upload
## Timp dezvoltare: ~3 zile (Ralph autonomous)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/modules/data_entry/services/receipt_service.py

@@ -15,6 +15,7 @@ from backend.modules.data_entry.schemas.receipt import (
     ReceiptFilter,
     ReceiptResponse,
     ReceiptListResponse,
+    ProcessingStats,
     AccountingEntryCreate,
 )
 from backend.modules.data_entry.services.expense_types import EXPENSE_TYPES, get_expense_type
@@ -53,17 +54,26 @@ class ReceiptService:
         session: AsyncSession,
         filters: ReceiptFilter,
     ) -> ReceiptListResponse:
-        """Get paginated list of receipts."""
+        """Get paginated list of receipts with processing_stats (US-012)."""
         receipts, total = await ReceiptCRUD.get_list(session, filters)
 
         pages = (total + filters.page_size - 1) // filters.page_size if total > 0 else 1
 
+        # Get processing stats for bulk uploaded receipts (US-012)
+        stats_dict = await ReceiptCRUD.get_processing_stats(
+            session,
+            company_id=filters.company_id,
+            batch_id=filters.batch_id,
+        )
+        processing_stats = ProcessingStats(**stats_dict)
+
         return ReceiptListResponse(
             items=[ReceiptResponse.model_validate(r) for r in receipts],
             total=total,
             page=filters.page,
             page_size=filters.page_size,
             pages=pages,
+            processing_stats=processing_stats,
         )
 
     @staticmethod