Soul S4: the Bifrost handoff notes, the Bifrost profile and the service
contract still named plaintext secret variables; each now names the _FILE
credential path. .env.example and the Spotiverse profile taught
GC_ACCESS_APP_SPOTIVERSE_SHARED_SECRET_FILE, which nothing reads: spotiverse
is not in appSlugs. Both lines are removed rather than adding the slug.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>