chore(release): candidate v2.0.19

[mega-maxwell]

Release candidate v2.0.19 (was 2.0.15).

Cut from 917ce10654a75269291b3cc97842816c82b2708d, which is not the tip of the default branch: release-v2.0.19 already exists at that commit, and merging this PR puts the version bump and the changelog entry on it. The default branch is left untouched — the next candidate syncs this entry back from the tag.

It creates no tag; the tag is cut once, at settlement, by release-settle → release-publish.

Changelog: this release's entry drafted under ## v2.0.19 (settle stamps the date on the release branch);
previous release's entry synced from its tag: inserted.

[github-actions]

Claude review status

Living comment — rewritten in place. The review workflow keeps this single comment up to date instead of posting a new one each round, so it always describes the latest reviewed commit and the earlier text is intentionally gone. No reply is needed here; answer findings and questions in the review threads it links to.

🛠️ Review did not finish

Attempted head c587ba0e · updated 2026-09-30T06:00:42+00:00

This round did not publish: MODEL_ACTION_FAILED in phase review_retry. Anything listed below is from the last round that did. Re-run the workflow or push a new commit to try again.