Review on #74658 flagged that the response-shape suite exercised identity,
ephemeral and upload paths but left two changed call sites untested:
- create_handoff_thread's seed-message ts (adapter.py:2262), which anchors
every subsequent handoff send onto the thread;
- the standalone media branch's chat_postMessage reads (adapter.py:8721 text
post, :8749 caption fallback), where an SDK-shaped reply used to drop the
ts and report a caption-only delivery as 'nothing deliverable'.
Both new cases run against the hand-rolled stand-in and the real
AsyncSlackResponse. Verified they fail against the pre-fix adapter.
Co-authored-by: Junie <junie@jetbrains.com>
Slack Web API calls return `SlackResponse`/`AsyncSlackResponse`, which are
mapping-like but not `dict` subclasses, so every `isinstance(resp, dict)`
gate took its "unexpected shape" branch at runtime: user and channel names
collapsed to raw IDs, every user resolved as a non-bot (defeating the
allow_bots loop guard), ephemeral replies were reported as failures, and
uploads/caption fallbacks lost their message_id.
Normalize responses through a single `_slack_response_payload()` helper
(dict passes through, SDK response yields `.data`, anything else yields
`{}` so callers keep their fallbacks) and use it at every call site.
Existing Slack tests injected plain dicts, which is why the defect was
invisible; the new tests run each behavioral case against a real
`AsyncSlackResponse` as well.
Will Lynas