docs: convert all skill instructions from npm to pnpm

Batch update 62 files across .claude/skills/ — SKILL.md, REMOVE.md,
and script files. Conversions: npm run -> pnpm run, npm install ->
pnpm install, npx -> pnpm exec/dlx, npm uninstall -> pnpm uninstall,
package-lock.json -> pnpm-lock.yaml, shebangs updated.

.claude/skills/debug/SKILL.md

@@ -41,7 +41,7 @@ Set `LOG_LEVEL=debug` for verbose output:
 
 ```bash
 # For development
-LOG_LEVEL=debug npm run dev
+LOG_LEVEL=debug pnpm run dev
 
 # For launchd service (macOS), add to plist EnvironmentVariables:
 <key>LOG_LEVEL</key>
@@ -231,7 +231,7 @@ query({
 
 ```bash
 # Rebuild main app
-npm run build
+pnpm run build
 
 # Rebuild container (use --no-cache for clean rebuild)
 ./container/build.sh