Probe: retrigger preview deploy

Empty commit to nudge the Preview viz workflow. The live preview at
viz-pythonbyexample.adewale-883.workers.dev still references the
pre-session site.css fingerprint (89fbe5e5f734), so the last five real
commits haven't been deployed.

https://claude.ai/code/session_01MazwoRWAihW6dwso3fMCHE

Author: claude