Add trading journal and portfolio tracking

app/api/routes.py

@@ -10,6 +10,7 @@ from database import connect
 from models import CATEGORIES, decimal_string
 from services import asset_service, income_service
 from api.auth import require_token
+from trading_models import TradingValidationError
 from api.schemas import (
     AssetCreate, AssetPatch, AssetResponse, AssetShareResponse, Category,
     CategoryShareResponse, IncomeCreate, IncomePatch, IncomeResponse,
@@ -30,6 +31,8 @@ class SafeAPIRoute(APIRoute):
                 # Never echo raw request bodies, credentials or internal exception context.
                 details = [{'loc': e['loc'], 'msg': e['msg'], 'type': e['type']} for e in error.errors()]
                 return JSONResponse({'detail': details}, status_code=422)
+            except TradingValidationError as error:
+                return JSONResponse({'detail': str(error)}, status_code=422)
             except ValueError:
                 return JSONResponse({'detail': 'Ungültige Werte. Bitte Felder und Position prüfen.'}, status_code=422)
             except sqlite3.IntegrityError: