Merge origin/main — the demo sign-in rename and a regenerated catalogue

No conflict in the source. `origin/main` renamed the seeded sign-ins after the
roles they open and regenerated the endpoint catalogue for it; both merged
clean, and the catalogue is regenerated once more here because this branch
moved two routes' line numbers as well.

Verified on the merged tree: 801 tests (482 unit, 319 integration), typecheck,
drift 0/0, security baseline unchanged, catalogue current.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: sameersegal