Previously a session could only be reassigned to another user via a
manual DB UPDATE. This adds it to the session edit UI for every owner of
a session (not just admins) - the ownership check in HandleUpdate
(existing.UserId == userId) already guarantees the caller owns the
session, so handing over one's own session is safe.
Backend:
- ProfileEndpoint: new GET /api/users returning a minimal user directory
(userId/username/displayName only) for any logged-in user. The
admin-gated /api/admin/users stays the source for sensitive fields
(defaultPath/canUseCli/isAdmin).
- SessionEndpoint.HandleUpdate: validate the target user exists (400 if
not) and pass allowUserReassign: true to UpdateSession.
- DatabaseService.UpdateSession: new allowUserReassign flag; only then is
a non-empty userId applied as user_id (empty/null is ignored - a
session must always have an owner).
Frontend:
- index.html: hidden #sessionOwnerRow with a user picker card in the
session edit form (existing sessions only).
- cards.js: buildUserCard helper for the picker.
- session-page.js: initSessionUserPicker loads users via apiGetUsers(),
preselects the current owner, and on an actual owner change asks for
confirmation (irreversible - the session leaves the user's own list).
- api.js: apiGetUsers() -> /api/users.
- ARCHITECTURE.md: document /api/users.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
