fix(ci): exclude E2E tests requiring Docker-in-Docker from CI

- Add missing pytest markers (e2e, requires_docker) to pyproject.toml
- Update CI workflow to skip E2E tests with -m "not e2e"
- Update integration test documentation with CI configuration notes
- E2E tests can still be run locally with: pytest -m e2e

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

pyproject.toml

@@ -156,6 +156,8 @@ markers = [
     "requires_external: Tests requiring external services (OpenAI, Azure, etc.)",
     "requires_db: Tests requiring database",
     "requires_redis: Tests requiring Redis",
+    "e2e: End-to-end tests with full infrastructure (requires Docker)",
+    "requires_docker: Tests requiring Docker containers (testcontainers)",
 ]
 
 # mypy configuration