Make MyPy happy

Fixes for various type errors throw by mypy.

portal/model/Uuid.py

@@ -26,7 +26,9 @@ class Uuid(types.TypeDecorator):
     def load_dialect_impl(self, dialect: Dialect) -> types.TypeEngine[Any]:
         return types.String(UUID_LENGTH)
 
-    def process_bind_param(self, value: str | UUID, dialect: Dialect) -> Optional[str]:
+    def process_bind_param(
+        self, value: Optional[str | UUID], dialect: Dialect
+    ) -> Optional[str]:
         if isinstance(value, str):
             # Manually create UUID from string, to raise an error if the string is malformed
             UUID(value)