chore: log my-publications handler steps
debugging why the toggle list shows empty even after the devlog account
created a site.standard.graph.subscription on its PDS. logs:
- entry (did + resolved pds url)
- PDS response size + first 120 bytes
- record count on success path
- explicit logs for the "no records key" / "not an array" early returns
- json parse failure includes a body preview
Co-Authored-By: Claude Opus 4 (1M context) <noreply@anthropic.com>