Python: use FOUNDRY_* settings in the ChatKit integration sample README

python/samples/05-end-to-end/chatkit-integration/README.md

@@ -135,7 +135,7 @@ async for event in stream_widget(thread_id=thread.id, widget=widget):
 
 - Python 3.11–3.15
 - Node.js 18.18+ and npm 9+
-- Azure OpenAI service configured
+- A Microsoft Foundry project with a deployed model
 - Azure CLI for authentication (`az login`)
 
 ### Network Requirements
@@ -169,15 +169,16 @@ For **production deployment**:
 
 ```bash
 cd python/samples/05-end-to-end/chatkit-integration
-pip install agent-framework-chatkit fastapi uvicorn azure-identity
+pip install agent-framework-chatkit agent-framework-foundry fastapi uvicorn azure-identity --pre
 ```
 
-2. **Configure Azure OpenAI:**
+2. **Configure Microsoft Foundry:**
+
+The backend creates its agent with `FoundryChatClient`, which reads these settings:
 
 ```bash
-export AZURE_OPENAI_ENDPOINT="https://your-resource.openai.azure.com/"
-export AZURE_OPENAI_API_VERSION="2024-06-01"
-export AZURE_OPENAI_MODEL="gpt-4o"
+export FOUNDRY_PROJECT_ENDPOINT="https://your-account.services.ai.azure.com/api/projects/your-project"
+export FOUNDRY_MODEL="gpt-4o"
 ```
 
 3. **Authenticate with Azure:**