review-dispatch

Single front door for code review. Resolves a target — working-tree changes, one PR, all open PRs, the last N commits, a time window, or a retrospective over merged history — into diffs, then routes to the right review engine (code-review for a quick gate, full-code-review for a deep or retro pass). Backs the /review command. Use when asked to review changes, a PR, multiple PRs, recent commits, or to run a commit retro, and the scope must be picked from an argument like "prs", "commits 10", "24h", or "retro 14d".