Critic review: Remove TINY_HARNESS_PUSH_KEY from the end-to-end architecture

The one critic round the operator's policy allows (the-loop critic policy: criticReviewCount: 1) could not complete: codex ran to the-loop's 900 s limit and returned no output. The round is recorded unavailable, which does not count as converged, so no independent-model review of this change exists yet. The human reviewer is told so in the PR briefing.

Review cycles

Round	Reviewer	Outcome	Findings → disposition	Link
1	[codex/gpt-6.1-sol] (the-loop critic run codex, THE_LOOP_SERVICE_LOCAL=1, --timeout 900)	unavailable — codex did not finish (ran 900s, the-loop's limit 900.0s); output empty, no token usage reported	—	PR #24 comment

Cause and what was done

• Started 12:09 PDT on 2026-10-11 and ended at the limit at 12:24 PDT. The JSON envelope reports ok: false and exitCode: -1, with empty output.
• Most likely cause: this machine's /tmp was at its per-user disk quota for the whole session, unrelated to the change. Every shell command in the session failed to write there, and codex keeps its session state under the system temporary directory.
• Not retried: the same quota would most likely stop a second run the same way, and another 15 minutes would buy no review. Re-run with the-loop critic run codex --work-item issue-23 once /tmp has space, and append the round here.
• The prompt used is the one in reference/reviewing.md's critic contract: the spec chain, the diff since e5b3d64, the security considerations, findings only, most severe first.