Switch pnpm->npm to fix esbuild build-script approval (matches astroreal)

- pnpm 11 (brew/corepack) errors 'ERR_PNPM_IGNORED_BUILDS: esbuild ignored'
  even with onlyBuiltDependencies; npm ci handles esbuild cleanly
- Moreminimore-astroreal uses npm ci + npm run build (proven on EasyPanel)
- Add esbuild as direct dep, generate package-lock.json, remove pnpm files
- Dockerfile: npm ci -> npm run build -> node server.js (port 4321)
- Verified: npm ci + npm run build produce dist (40 pages) successfully

Dockerfile

@@ -1,8 +1,8 @@
 # ── มิตซูชัยพร — Astro + Express (static) ─────────────────────────
-# Build: pnpm build (astro) → Runtime: node server.js (port 4321)
+# Build: npm run build (astro) → Runtime: node server.js (port 4321)
 #
-# Mirrors moreminimore-astroreal deployment pattern that works on EasyPanel:
-# serve the static Astro build from a small Node/Express server (no nginx).
+# Uses npm (like moreminimore-astroreal which deploys on EasyPanel).
+# esbuild builds cleanly with npm ci (no pnpm build-script approval issues).
 #
 # Env: PORT (default 4321), GA_ID, FORM_EMAIL, GMAP_LAT/LNG (see .env.example)
 
@@ -10,16 +10,15 @@ FROM node:22-bookworm-slim
 
 WORKDIR /app
 
-# ── Dependencies (pnpm 11 to match lockfile) ─────────────────────
-COPY package.json pnpm-lock.yaml ./
-RUN corepack enable && corepack prepare pnpm@11 --activate \
-    && pnpm install --frozen-lockfile
+# ── Dependencies ──────────────────────────────────────────────────
+COPY package.json package-lock.json ./
+RUN npm ci
 
 # ── Source + Build ───────────────────────────────────────────────
 COPY astro.config.mjs tsconfig.json ./
 COPY src/ src/
 COPY public/ public/
-RUN pnpm build
+RUN npm run build
 
 # ── Runtime ──────────────────────────────────────────────────────
 COPY server.js ./