The helper landed in #2376 and is exercised via chat_files + registry
integration tests. Those tests conflate the helper's behavior with the
caller's response shape — a future refactor that broke the (secret,
healed, err) contract subtly (e.g. returning healed=true on a
read-success path, or swallowing a mint error) might still pass them.
Adds 4 direct sub-tests pinning each branch of the contract:
- secret already present → (s, false, nil)
- secret missing, mint succeeds → (minted, true, nil)
- secret missing, mint fails → ("", false, err)
- read fails (non-NoInboundSecret) → ("", false, err)
Each sub-case asserts the return tuple shape AND mock.ExpectationsWereMet
(for the success path) so a future helper change that skips a DB op
trips the gate immediately.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>