Admin-facing. Extends the existing API-token UI: an 'agency' scope option reveals a
playlist picker (the workspace's playlists); creating the token binds the checked ones as
its allowlist (target_playlist_ids). The token list shows each agency token's designated
playlists (tokens GET now returns targets for agency-scoped tokens). i18n keys added across
all five locales (parity test).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>