Patching preview text then delivering media separately splits a captioned-file
reply into two posts: a text-only preview + captionless file attachment.
New logic in the isFinal branch:
- Text-only payload: patch in place as before (no change for common case)
- Media payload: skip the patch, reset state, deliver full payload via
deliverMattermostReplyPayload (text+media together), then delete preview.
- Patch failure: same fallback as media payload — full delivery + delete.
6bea6df33f