zed is registered, registrar-aligned and registry-tested, but it was the
only one of the 34 integrations absent from integrations/catalog.json,
making it undiscoverable through the discovery manifest. Add the missing
'zed' entry (mirroring the sibling skills entries) and a registry<->catalog
parity regression test so a future integration can't silently drift.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>