chore(caveman): purge plugin + always-on integration

Disable + uninstall caveman@caveman and delete every repo dependency on
it: SessionStart/UserPromptSubmit hook blocks, standalone hook files,
settings.json enabledPlugins + marketplace entries, install-plugins.sh
STEP 5.5, update-all.sh refresh step, plugins.lock.json entry, doctor.sh
checks, lib/detect-plugins.sh helpers, lib/profile.sh + plugin-advisor +
skills/profile protected-list entries, .gitignore runtime-file block,
and README/USAGE docs. Dead /caveman:compress refs replaced with
manual/claude.ai guidance. Memory-registry terse-format convention kept
(separate subsystem). Version 3.4.0 -> 3.5.0.

On a subscription plan caveman's ~75% output-token compression has no
cost benefit, and the always-on hooks added friction on validation
gates and client deliverables.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01X3e8LaH2vymmxyh36h3jFU

lib/detect-plugins.sh

@@ -66,12 +66,6 @@ detect_graphifyy() {
   command -v graphify &>/dev/null
 }
 
-detect_caveman() {
-  # Caveman — output-token compression via caveman-speak (marketplace plugin)
-  local cache_dir="$HOME/.claude/plugins/cache"
-  [ -d "$cache_dir" ] && compgen -G "$cache_dir"/*caveman* &>/dev/null
-}
-
 # True if a plugin is registered as enabled in settings.json's
 # enabledPlugins map. Filesystem only (no subprocess to claude CLI).
 # Argument is the full "name@marketplace" key.
@@ -81,19 +75,6 @@ plugin_enabled() {
   grep -qE "\"${key}\"[[:space:]]*:[[:space:]]*true" "$HOME/.claude/settings.json"
 }
 
-detect_caveman_hooks() {
-  # Standalone hooks (statusline + stats) deployed by caveman hooks/install.sh
-  [ -f "$HOME/.claude/hooks/caveman-statusline.sh" ]
-}
-
-detect_caveman_shrink() {
-  # caveman-shrink is a proxy — only valid when registered with an
-  # upstream wrapper (e.g. caveman-shrink-fs:, caveman-shrink-github:).
-  # Bare 'caveman-shrink:' fails health checks and is treated as missing.
-  command -v claude &>/dev/null \
-    && claude mcp list 2>/dev/null | grep -q '^caveman-shrink-'
-}
-
 
 # --- Plan detection ---