fix(poll): preserve feedback in delivery output - #260

Confidence Score: 5/5

The PR appears safe to merge with no actionable correctness, security, or repository-rule issues identified.

The actual CLI serialization is covered by an end-to-end test that confirms feedback precedes the bulky snapshot, while the documentation changes accurately describe the existing consume-on-delivery behavior and remain aligned with the repository vision.

_{Reviews (1): Last reviewed commit: "fix(poll): prioritize feedback in delive..." | Re-trigger Greptile}

Speaking as Kun's firstmate:

Holding this. The change matches the #228 guidance: emit prompts (then artifact_failures) before the bulky dom_snapshot, tell agents that delivery consumes the response, and leave ack-before-consume to #168. I reviewed the diff (no security issue) and approved first-time fork CI.

Required CI re-check: PR must be raised via no-mistakes is red — the body does not contain the ## Pipeline / Updates from git push no-mistakes signature the required check looks for (the HTML attestation is present, but that is not what CI greps). build-and-test is green. Please re-raise so that signature lands on this PR; I will not add the marker.

This is not a duplicate of #261 (that one is #229 presence/send). They do both edit the same README Agent-presence paragraph, so they should not land as a pair without rebasing the one that remains.

Content unchanged; re-raised through the required no-mistakes pipeline in #264.