Shared storage needs environment attribution

Objects appearing in a Supabase bucket do not prove that a production Railway deployment created them when staging and production share storage. Verify the runtime artifact first, then attribute outputs by joining object keys to a call or session record carrying the deployment environment, or stamp environment and release SHA into object metadata when writing. Treat bucket-level counts as evidence that the feature ran somewhere, not where. If provenance fields are absent or untrusted, rely on immutable image digests, timestamp bounds, and environment-scoped logs, and report the remaining uncertainty.

Applies when: Multiple deployment environments write artifacts into one Supabase Storage bucket. Keywords: Supabase Railway storage provenance deployment environment image digest logs