* feat(scripts): add watch-pr-ci CI watcher with mergeable and attach prechecks
* fix(scripts): require successful attached PR CI run
* fix(scripts): harden watch-pr-ci verdicts against foreign runs and truncated rollups
* fix(scripts): add fresh-run gating to watch-pr-ci attachment
* fix(scripts): guard stale-cancelled verdict against truncated context pages
* fix(scripts): declare rollup context total count
* fix(scripts): sanitize check names and close the final polling interval
* test(scripts): type deadline wait samples