Dotfiles Debugging Playbook

Symptom-to-fix triage for this dotfiles repo. Load when something is BROKEN and you need to diagnose it -- plugin skills/commands missing from a session, settings.json truncated, dangling or write-through symlinks, "git refuses to commit" or wrong commit identity, SSH offering the wrong key, a guard hook blocking a commit, a cloud session missing its config, blank statusline, dead hooks, zsh nags, prettier rewriting files unexpectedly, or a worktree missing .todos/.planning. Trigger phrases: "why is X missing", "commit blocked", "hook didn't run", "wrong identity", "symlink broken", "plugin not installed". NOT for routine operation (dotfiles-run-and-operate), proving heal…