Add streaming support to Gemini provider and implement generate_stream_text method

simplemind/providers/gemini.py

@@ -24,6 +24,7 @@ DEFAULT_MODEL = "models/gemini-1.5-flash-latest"
 class Gemini(BaseProvider):
     NAME = PROVIDER_NAME
     DEFAULT_MODEL = DEFAULT_MODEL
+    supports_streaming = True
 
     def __init__(self, api_key: str | None = None):
         self.api_key = api_key or settings.get_api_key(PROVIDER_NAME)
@@ -107,3 +108,17 @@ class Gemini(BaseProvider):
             # Handle the exception appropriately, e.g., log the error or raise a custom exception
             raise RuntimeError(f"Failed to generate text with Gemini API: {e}") from e
         return response.text
+
+    @logger
+    def generate_stream_text(self, prompt: str, **kwargs) -> str:
+        """Generate streaming text using the Gemini API."""
+        kwargs.pop("llm_model", None)
+        try:
+            response = self.client.generate_content(prompt, stream=True, **kwargs)
+            for chunk in response:
+                if chunk.text:
+                    yield chunk.text
+        except Exception as e:
+            raise RuntimeError(
+                f"Failed to generate streaming text with Gemini API: {e}"
+            ) from e