fix: remaining npm→pnpm gaps + dockerignore for pnpm symlinks

- container/.dockerignore (new): exclude agent-runner/node_modules and
  agent-runner/dist so COPY agent-runner/ ./ doesn't clobber the
  pnpm-installed node_modules with host directories. Under npm's flat
  layout this was forgiving; under pnpm's symlink layout it's a hard
  conflict (overlay2 cannot copy onto a symlink target).
- setup/{groups,service}.ts: execSync('pnpm run build') not npm.
- setup/index.ts: usage string.
- scripts/*.ts: usage comments + seed-discord final log.
- .claude/settings.json: permission allowlist entries.
- .claude/skills/{add-whatsapp-v2,add-dashboard}/SKILL.md: docs.
- container/skills/{frontend-engineer,vercel-cli,self-customize}/SKILL.md:
  agent-facing docs still told the container agent to run npm.

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

.claude/skills/add-dashboard/SKILL.md

@@ -25,7 +25,7 @@ NanoClaw (pusher)              Dashboard (npm package)
 ### 1. Install the npm package
 
 ```bash
-npm install @nanoco/nanoclaw-dashboard
+pnpm install @nanoco/nanoclaw-dashboard
 ```
 
 ### 2. Copy the pusher module
@@ -94,7 +94,7 @@ Generate the secret: `node -e "console.log('nc-' + require('crypto').randomBytes
 ### 6. Build and restart
 
 ```bash
-npm run build
+pnpm run build
 systemctl --user restart nanoclaw   # Linux
 # or: launchctl kickstart -k gui/$(id -u)/com.nanoclaw  # macOS
 ```
@@ -130,9 +130,9 @@ Open `http://localhost:3100/dashboard` in a browser.
 ## Removal
 
 ```bash
-npm uninstall @nanoco/nanoclaw-dashboard
+pnpm uninstall @nanoco/nanoclaw-dashboard
 rm src/dashboard-pusher.ts
 # Remove the dashboard block from src/index.ts
 # Remove DASHBOARD_SECRET and DASHBOARD_PORT from .env
-npm run build
+pnpm run build
 ```