document uv run --with pattern and tangled data source
- CLAUDE.md: fix stale worker image (3.11→3.14), add command override
pattern, per-deployment python version, requires-python rationale
- journey.md: add steps 10-11 covering ephemeral flow environments,
per-deployment python overrides, tangled.org data pipeline, and
upstream improvement candidates
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>