approval-authorizer legacy titles

Trap: retaining PUBLISH_TITLE_REGEX beside the generated parser looks useful for authorization compatibility, but creates parser drift between approval, CI, and publication. Fix: use generated parsePublishIssueTitle() plus shared validators everywhere; parsePublishTitle() remains non-throwing and returns null for authorization failures. Edit src/modules/publish-issue-title.peggy and regenerate—never hand-edit or merge publish-issue-title.js.