The encryption key must never be retrievable through the app (that would undo
the whole point of TOKEN_ENCRYPTION_KEY — a stolen session/XSS could then read
the master key). Instead surface a non-reversible fingerprint so operators can:
- verify which key is currently active,
- confirm a running instance matches the key they backed up, and
- spot an accidental key change (which would make existing secrets unrecoverable).
- encryptionService.keyFingerprint(): domain-separated SHA-256 prefix of the
active key (env if set, else the stored DB key); never force-creates a key
(returns null when none exists), shares nothing with the cipher derivation.
- admin bank-sync-config exposes key_fingerprint alongside encryption_key_source.
- Admin Bank Sync card renders it with backup guidance.
- Test: stable per key, differs by key, not reversible / not the raw key.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
1457de487f