Rebuild card UI bundle for dag.svelte changes

The dag.svelte changes in 211618d (Fix start/end step regressions)
added flow-without-start/end rendering support but were never bundled
into main.js. CI does not rebuild the card UI, so the deployed cards
have been rendering against stale bundled code.

Re-run `npm run build` in metaflow/plugins/cards/ui/ to regenerate
the bundle from the current Svelte source.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: talsperre