Python: Add samples syntax checking with pyright (#3710)

* Add samples syntax checking with pyright

- Add pyrightconfig.samples.json with relaxed type checking but import validation
- Add samples-syntax poe task to check samples for syntax and import errors
- Add samples-syntax to check and pre-commit-check tasks
- Fix 78 sample errors:
  - Update workflow builder imports to use agent_framework_orchestrations
  - Change content type isinstance checks to content.type comparisons
  - Use Content factory methods instead of removed content type classes
  - Fix TypedDict access patterns for Annotation
  - Fix various API mismatches (normalize_messages, ChatMessage.text, role)

* fixed a bunch of samples and tweaks to pre-commit

* updated lock

* updated lock

* fixes

* added lint to samples

python/samples/getting_started/middleware/chat_middleware.py

@@ -10,6 +10,7 @@ from agent_framework import (
     ChatMessage,
     ChatMiddleware,
     ChatResponse,
+    MiddlewareTermination,
     chat_middleware,
     tool,
 )
@@ -127,8 +128,7 @@ async def security_and_override_middleware(
                     )
 
                     # Set terminate flag to stop execution
-                    context.terminate = True
-                    return
+                    raise MiddlewareTermination
 
     # Continue to next middleware or AI execution
     await next(context)