Adds the /api/me/* slice mirroring flutter_client's SettingsApi:
* GET /api/me → MyProfile (id / username / displayName / email / isAdmin)
* PUT /api/me/profile → merges displayName + email
* PUT /api/me/password → current + new password
No caching — the Settings cards fetch on mount and writes go
straight to the server. No offline-queue fallback (changing your
own password offline is meaningless).
Profile + Password UI cards land in the next commit; this is just
the data layer.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen
f18b7d4658