chore: bring examples under pyright (#43)

VS Code's Pylance surfaces type errors on the example files because
they're outside pyright's `[tool.pyright].include` (currently src,
tests). Pylance reads the project config, sees the example file isn't
in scope, falls back to inferred typing that loses pydantic / openai
SDK type info, and emits unknown-member squiggles.

Two changes:

- pyproject.toml: extend pyright's include to ["src", "tests",
  "examples"] so the project-wide check covers them and Pylance
  inherits the same scope.

- examples/00-hello-world/main.py: with pyright now seeing the
  example, the trace() observer's `event.post_state.sources` access
  becomes a real error. `NodeEvent.post_state` is typed as the base
  `State`, not the subclass `PipelineState`. Adding an
  `isinstance(event.post_state, PipelineState)` check narrows the
  type for static checkers and acts as a defensive guard against any
  foreign-state observer event the engine might dispatch.

All other examples (01-05) come up pyright-clean under project-wide
context. Confirmed via uv run pyright = 0 errors after the changes.

Author: chris-colinsky

examples/00-hello-world/main.py

@@ -178,8 +178,12 @@ def route(state: PipelineState) -> str:
 async def trace(event: NodeEvent) -> None:
     # OpenAIProvider emits NodeEvent-shaped events for LLM-span
     # tracking under a sentinel namespace; those have post_state=None.
-    # Filter to events that carry a state snapshot before reading it.
-    if event.phase == "completed" and event.error is None and event.post_state is not None:
+    # Filter to events that carry a PipelineState snapshot before
+    # reading it. The isinstance check both narrows the type for
+    # static checkers (post_state is typed as the base State, not
+    # PipelineState) and acts as a defensive guard against any
+    # foreign-state observer event the engine might dispatch.
+    if event.phase == "completed" and event.error is None and isinstance(event.post_state, PipelineState):
         print(f"{event.node_name}: sources={event.post_state.sources}")
 
 

pyproject.toml

@@ -79,7 +79,7 @@ examples = [
 packages = ["src/openarmature"]
 
 [tool.pyright]
-include = ["src", "tests"]
+include = ["src", "tests", "examples"]
 pythonVersion = "3.12"
 typeCheckingMode = "strict"
 reportMissingTypeStubs = false