feat: Add multiple TVA entries support for Romanian receipts

- Add TvaEntry schema supporting multiple TVA rates (A, B, C, D codes)
- Update OCR extractor to extract multiple TVA entries from receipts
- Support both old (19%, 9%, 5%) and new Romanian rates (21%, 11% from Aug 2025)
- Add tva_breakdown, tva_total, items_count, vendor_address to Receipt model
- Update OCRPreview.vue to display TVA entries with rate badges
- Add "Detalii Suplimentare" section in ReceiptCreateView with editable TVA table
- Add TVA breakdown display in ReceiptDetailView
- Create database migration for new TVA columns

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

data-entry-app/backend/app/schemas/receipt.py

@@ -64,6 +64,15 @@ class AttachmentResponse(BaseModel):
     uploaded_at: datetime
 
 
+# ============ TVA Schema ============
+
+class TvaEntrySchema(BaseModel):
+    """Single TVA entry with code, percentage and amount."""
+    code: Optional[str] = Field(default=None, description="TVA code: A, B, C, D")
+    percent: int = Field(description="TVA percentage: 0, 5, 9, 19, 21")
+    amount: Decimal = Field(description="TVA amount for this rate")
+
+
 # ============ Receipt Schemas ============
 
 class ReceiptBase(BaseModel):
@@ -75,6 +84,12 @@ class ReceiptBase(BaseModel):
     receipt_date: date
     amount: Decimal = Field(gt=0)
     description: Optional[str] = Field(default=None, max_length=500)
+    # TVA info (multiple entries support)
+    tva_breakdown: Optional[List[TvaEntrySchema]] = Field(default=None, description="List of TVA entries")
+    tva_total: Optional[Decimal] = Field(default=None, description="Total TVA amount")
+    items_count: Optional[int] = Field(default=None, description="Number of items")
+    vendor_address: Optional[str] = Field(default=None, max_length=500, description="Vendor address")
+    # Other fields
     expense_type_code: Optional[str] = Field(default=None, max_length=20)
     company_id: int
     partner_id: Optional[int] = None
@@ -98,6 +113,12 @@ class ReceiptUpdate(BaseModel):
     receipt_date: Optional[date] = None
     amount: Optional[Decimal] = Field(default=None, gt=0)
     description: Optional[str] = Field(default=None, max_length=500)
+    # TVA info (multiple entries support)
+    tva_breakdown: Optional[List[TvaEntrySchema]] = Field(default=None, description="List of TVA entries")
+    tva_total: Optional[Decimal] = Field(default=None, description="Total TVA amount")
+    items_count: Optional[int] = Field(default=None, description="Number of items")
+    vendor_address: Optional[str] = Field(default=None, max_length=500, description="Vendor address")
+    # Other fields
     expense_type_code: Optional[str] = Field(default=None, max_length=20)
     partner_id: Optional[int] = None
     partner_name: Optional[str] = Field(default=None, max_length=200)