fix(ci): write Craft publish-state file so retries skip already-published targets (#449)

The Publish workflow was missing the equivalent of getsentry/publish's
"Set targets" step. When a publish partially fails (e.g. npm returns
E401 after actually publishing), retrying would fail with "cannot
publish over previously published versions" because Craft didn't know
which targets already succeeded.

This adds:
1. **Set already-published targets** step: parses checked targets from
the publish issue body and writes a Craft publish-state file so Craft
skips them
2. **Update published targets in issue** step: on failure/cancel, reads
Craft's state file and checks off successfully published targets in the
issue body for the next retry

Modelled after getsentry/publish's workflow.