[rewrite] Updated models a bit, preparing to make first functional routes

backend/app/utils/database_exception_catcher.py

@@ -0,0 +1,13 @@
+from functools import wraps
+from sqlalchemy.exc import DatabaseError as SqlAlchemyDatabaseError
+from app.database.exceptions import DatabaseError
+
+
+def handle_database_errors(func):
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        try:
+            return func(*args, **kwargs)
+        except SqlAlchemyDatabaseError as e:
+            raise DatabaseError(str(e), -1) from e
+    return wrapper