Add payment line parser and fix OCR override from payment_line

- Add MachineCodeParser for Swedish invoice payment line parsing
- Fix OCR Reference extraction by normalizing account number spaces
- Add cross-validation tests for pipeline and field_extractor
- Update UI layout for compact upload and full-width results

Key changes:
- machine_code_parser.py: Handle spaces in Bankgiro numbers (e.g. "78 2 1 713")
- pipeline.py: OCR and Amount override from payment_line, BG/PG comparison only
- field_extractor.py: Improved invoice number normalization
- app.py: Responsive UI layout changes

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

src/web/config.py

@@ -13,8 +13,8 @@ from typing import Any
 class ModelConfig:
     """YOLO model configuration."""
 
-    model_path: Path = Path("runs/train/invoice_yolo11n_full/weights/best.pt")
-    confidence_threshold: float = 0.3
+    model_path: Path = Path("runs/train/invoice_fields/weights/best.pt")
+    confidence_threshold: float = 0.5
     use_gpu: bool = True
     dpi: int = 150