[Bug]: Editing a GitLab comment never wakes a PR watcher #30402

Area

Pull requests (GitLab provider), PR watching

Steps to reproduce

1. Have an agent watch a GitLab merge request with watch_pull_request.
2. Edit an existing comment on that merge request, the way CI and review bots update one summary comment in place instead of posting a new one.

Expected behavior

The watcher wakes for the edited comment, as it does on GitHub and Forgejo.

Actual behavior

Nothing happens. The watcher sees a remark as new when editedAt ?? createdAt passes its watermark, and the GitLab adapter never sets editedAt. So only brand-new notes wake it.

GitLab has the data, but the obvious fields lie. REST updated_at and GraphQL lastEditedAt both move when a thread is resolved or reopened, on every note in that thread. Only lastEditedBy stays null until someone changes the text. On TonybynMp4/git-ansible!5, after editing note 4154544846 and resolving then reopening an unedited thread:

{"id":"4154544846","createdAt":"2026-11-03T20:43:32Z","lastEditedAt":"2026-11-03T21:25:43Z","by":"TonybynMp4","resolved":false}
{"id":"4154544931","createdAt":"2026-11-03T20:43:33Z","lastEditedAt":"2026-11-03T21:25:54Z","by":null,"resolved":false}
{"id":"4154730801","createdAt":"2026-11-03T21:14:22Z","lastEditedAt":"2026-11-03T21:25:54Z","by":null,"resolved":false}

Impact

An agent waiting on a bot that edits its comment (test summaries, Danger, coverage reports) waits forever on GitLab.

Version or commit

aee76a8b47 (main)

Environment

Linux, gitlab.com through glab.

Workaround

None.