refactor: enforce BasedPyright strict type checking (#5158)

AGENTS.md

@@ -11,6 +11,11 @@ nanobot is a lightweight, open-source AI agent framework written in Python with
 pytest tests/test_openai_api.py::test_function -v
 ruff check nanobot/
 
+# Strict type checking (matches CI)
+uv sync --all-extras --dev
+uv run --no-sync python -m scripts.install_channel_dependencies --all-channels
+uv run --no-sync basedpyright
+
 # WebUI: dev server (proxies API/WS to gateway :8765), build, test
 # Build outputs to ../nanobot/web/dist (bundled into the Python wheel)
 cd webui && bun run dev      # or NANOBOT_API_URL=... bun run dev