Add TOTP export via CLI and API

docs/api_reference.md

@@ -27,6 +27,7 @@ Keep this token secret. Every request must include it in the `Authorization` hea
 - `POST /api/v1/fingerprint` – Add a new seed fingerprint.
 - `DELETE /api/v1/fingerprint/{fp}` – Remove a fingerprint.
 - `POST /api/v1/fingerprint/select` – Switch the active fingerprint.
+- `GET /api/v1/totp/export` – Export all TOTP entries as JSON.
 - `GET /api/v1/nostr/pubkey` – Fetch the Nostr public key for the active seed.
 - `POST /api/v1/checksum/verify` – Verify the checksum of the running script.
 - `POST /api/v1/checksum/update` – Update the stored script checksum.