slop-review

Open the native, Monaco-powered diff review window so the user can leave inline / file-level / overall comments on the current changes (the AI slop), then address each comment. Use this when the user asks to "review my changes", "review the slop", "review my diff", "open a diff review", "open the review window", "get feedback on my work", "do a PR-style review", "show me what I changed and let me comment", or types `@slop-review` explicitly. Defaults to a PR-style review of all commits + uncommitted changes since the merge-base with the auto-detected base branch (origin/HEAD → origin/main → main → origin/master → master); also supports last-commit, uncommitted, and all-files modes.