feat(effort): entry level on every skill next to its model pin (BDR-108)

- lib/effort-pins.txt (map) + lib/effort-pins.sh (idempotent re-apply)
  replace the hardcoded brainstorming/writing-plans loop; called after the
  last vendoring step of install-plugins.sh AND update-all.sh (the resync
  dropped the pins until the next make plugin)
- design stack high uniform (last loaded wins), superpowers, agent-skills,
  21st pack pinned from the map; skills-perso low, pdf-translate medium,
  site-motion high
- doctrine: design stack loads paired with the first Read; one level per
  stack (CLAUDE.global.md, lib/effort-shift.md)
- lib/effort-audit.py prints thinking coverage per scope (sub-agent records
  carry no thinking count on ~94 % of requests)
- census map-driven + fixture suite lib/tests/effort-pins.test.sh; docs
  README/USAGE/CHANGELOG; contract + TODO plan

install-plugins.sh

@@ -934,16 +934,9 @@ for _ext_skill in "${EXT_SKILL_NAMES[@]}"; do
 done
 echo ""
 
-# Effort tiering (BDR-107): the vendored brainstorming/writing-plans carry an
-# effort pin upstream lacks; re-apply after every resync (census lock in
-# lib/tests/effort-routing.test.sh alarms if this ever stops working).
-for _s in brainstorming writing-plans; do
-  _f="$(cd "$(dirname "$0")" && pwd)/skills-external/$_s/SKILL.md"
-  if [ -f "$_f" ] && ! grep -q '^effort:' "$_f"; then
-    sed -i "0,/^name: $_s\$/s//&\neffort: xhigh/" "$_f"
-  fi
-done
-unset _s _f
+# Effort pins (BDR-107, BDR-108): every vendored external gets its entry
+# level from lib/effort-pins.txt, re-applied ONCE after the last vendoring
+# step (the 21st pack, STEP 8.7) — see apply_effort_pins there.
 
 # ============================================================
 # STEP 8.5 — EXTERNAL SKILLS (npx skills add …)
@@ -1062,6 +1055,13 @@ if command -v 21st &>/dev/null; then
   rm -rf "$TFD_STAGE"
 fi
 
+# Effort pins (BDR-107, BDR-108): the vendored externals carry no `effort:`
+# upstream and every vendoring step above rewrites SKILL.md. Re-apply the
+# entry levels from lib/effort-pins.txt once, after the LAST such step.
+# shellcheck source=lib/effort-pins.sh disable=SC1091
+source "$REPO/lib/effort-pins.sh"
+apply_effort_pins "$REPO" || warn "effort pins: map lines rejected — fix lib/effort-pins.txt"
+
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