Agent Skills: blitz-merge

Batch-fix all open bugs in parallel, iterate on PR reviews until clean, then squash-merge each PR sequentially. Extends bug-blitz with automated review cycles and merge. Fetches bug-type tasks from Transit, creates worktrees, spawns parallel fix agents, runs /pr-review-fixer in a loop until no blockers/critical/major issues remain, then merges PRs one by one with squash-and-merge.