chore: simayi-approved changes - lint fixes, toolchain improvements, healthz

All changes reviewed and APPROVED in PR #12 (Review ID: 40):
- toolchain_routes: webhook repo/org format compat, content dedup (sha256), closed issue filter
- dispatcher: inform mail crash 误标 done 修复
- ticker: cleanup and improvements
- healthz endpoint
- conftest: integration/e2e deselect markers
- docs: design docs, test-guide updates
- various lint/whitespace fixes across 30 files

pyproject.toml

@@ -8,8 +8,10 @@ requires-python = ">=3.9"
 asyncio_mode = "auto"
 testpaths = ["tests"]
 markers = [
-    "integration: real agent tests (requires RUN_INTEGRATION=1)",
+    "integration: integration tests (requires RUN_INTEGRATION=1)",
+    "e2e: end-to-end tests with real daemon + Agent (requires RUN_INTEGRATION=1)",
 ]
+# Default deselection of integration/e2e handled in conftest.py pytest_collection_modifyitems
 
 [tool.pyright]
 venvPath = "."