feat: Add WhatsApp import scripts for receipt processing

- OCR client for SQLite queue
- WhatsApp flow: PDF -> OCR -> SQLite -> Oracle
- PACK_CONTAFIN integration for Oracle save
- README with flux documentation

backend/scripts/whatsapp_import/conftest.py

@@ -0,0 +1,13 @@
+"""
+Root pytest configuration for ROA2WEB.
+
+Ensures proper Python path setup for all test imports.
+"""
+
+import sys
+from pathlib import Path
+
+# Add project root to Python path at import time
+project_root = Path(__file__).parent
+if str(project_root) not in sys.path:
+    sys.path.insert(0, str(project_root))