feat(caveman): full install — plugin + standalone hooks + MCP scaffold

Wires JuliusBrussee/caveman into the always-on tier alongside
security-guidance and superpowers. Caveman compresses Claude's output
tokens (~75%) by speaking like a caveman while keeping technical
substance. Three layers:

  1. Plugin (caveman@caveman, marketplace JuliusBrussee/caveman)
     — adds /caveman, /caveman-commit, /caveman-review, /caveman-stats,
       /caveman-help, /cavecrew, /compress + 3 cavecrew agents +
       SessionStart/UserPromptSubmit hooks from the plugin path.
  2. Standalone hooks (statusline + stats badge) deployed by
     caveman's own hooks/install.sh into ~/.claude/hooks/. Paths in
     settings.json normalized to ~/.claude/hooks/... so this user's
     home dir doesn't leak across machines.
  3. caveman-shrink MCP proxy — NOT auto-registered. The bare proxy
     fails health checks because it requires an upstream MCP server
     to wrap. install-plugins.sh STEP 5.5 prints a snippet showing how
     to register a wrapped entry (e.g. caveman-shrink-fs) when the user
     decides which upstream to compress.

New helper enable_plugin() for explicit always-on activation —
'claude plugin install' only copies into cache, doesn't write
enabledPlugins. Idempotent via Python json check.

doctor.sh adds detect_caveman / detect_caveman_hooks / detect_caveman_shrink
checks plus a 300t passive-cost adder. update-all.sh refreshes hook
files via the upstream installer's --force mode.

.gitignore covers caveman runtime files materialized into hooks/
because ~/.claude/hooks is symlinked to this repo.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -56,6 +56,18 @@ skills/find-skills
 # Staging area used by lib/toggle-external.sh when disabling a tool
 skills-disabled/
 
+# Caveman runtime hook files — deployed by caveman hooks/install.sh into
+# ~/.claude/hooks/ (which is a symlink to this repo's hooks/), so they
+# materialize here. They are user-scope state, not repo source.
+hooks/caveman-activate.js
+hooks/caveman-config.js
+hooks/caveman-mode-tracker.js
+hooks/caveman-stats.js
+hooks/caveman-statusline.sh
+hooks/package.json
+hooks/package-lock.json
+hooks/node_modules/
+
 # Local project config (per-machine, not shared)
 .claude/*
 !.claude/tasks/