feat: added finish_reason

Author: davide-andreoli

pydantic_ai_slim/pydantic_ai/models/gemini.py

@@ -274,10 +274,15 @@ def _process_response(self, response: _GeminiResponse) -> ModelResponse:
                 )
         parts = response['candidates'][0]['content']['parts']
         vendor_id = response.get('vendor_id', None)
+        vendor_details = {'finish_reason': response['candidates'][0].get('finish_reason')}
         usage = _metadata_as_usage(response)
         usage.requests = 1
         return _process_response_from_parts(
-            parts, response.get('model_version', self._model_name), usage, vendor_id=vendor_id
+            parts,
+            response.get('model_version', self._model_name),
+            usage,
+            vendor_id=vendor_id,
+            vendor_details=vendor_details,
         )
 
     async def _process_streamed_response(self, http_response: HTTPResponse) -> StreamedResponse:
@@ -600,7 +605,11 @@ def _function_call_part_from_call(tool: ToolCallPart) -> _GeminiFunctionCallPart
 
 
 def _process_response_from_parts(
-    parts: Sequence[_GeminiPartUnion], model_name: GeminiModelName, usage: usage.Usage, vendor_id: str | None
+    parts: Sequence[_GeminiPartUnion],
+    model_name: GeminiModelName,
+    usage: usage.Usage,
+    vendor_id: str | None,
+    vendor_details: dict[str, Any] | None,
 ) -> ModelResponse:
     items: list[ModelResponsePart] = []
     for part in parts:
@@ -612,7 +621,9 @@ def _process_response_from_parts(
             raise UnexpectedModelBehavior(
                 f'Unsupported response from Gemini, expected all parts to be function calls or text, got: {part!r}'
             )
-    return ModelResponse(parts=items, usage=usage, model_name=model_name, vendor_id=vendor_id)
+    return ModelResponse(
+        parts=items, usage=usage, model_name=model_name, vendor_id=vendor_id, vendor_details=vendor_details
+    )
 
 
 class _GeminiFunctionCall(TypedDict):