fix: yield form in fastui_form to keep file handler open

Author: gradient-ascent-ai-lab

src/python-fastui/fastui/forms.py

@@ -38,13 +38,13 @@ async def run_fastui_form(request: fastapi.Request):
         async with request.form() as form_data:
             model_data = unflatten(form_data)
 
-        try:
-            return model.model_validate(model_data)
-        except pydantic.ValidationError as e:
-            raise fastapi.HTTPException(
-                status_code=422,
-                detail={'form': e.errors(include_input=False, include_url=False, include_context=False)},
-            )
+            try:
+                yield model.model_validate(model_data)
+            except pydantic.ValidationError as e:
+                raise fastapi.HTTPException(
+                    status_code=422,
+                    detail={'form': e.errors(include_input=False, include_url=False, include_context=False)},
+                )
 
     return fastapi.Depends(run_fastui_form)