HALOZER WhatsApp Web Service v37

IMPORTANT:
- Keep the existing .wwebjs_auth folder. Do NOT delete it; it contains the saved WhatsApp session.
- Deploy only after stopping the current wa.manage.halozer.in Node app.
- Replace server.js and package.json, then run NPM Install once.
- Start the wa.manage.halozer.in Node app.
- Open /health first. If the existing session is valid, it may authenticate without a new QR. If has_qr becomes true, open /qr and scan it.
- Do not run multiple copies of this service.

v37 changes from v36:
- Reconciled the actual v36 failure: Protocol error (Network.setUserAgentOverride): Session closed during Client.initialize().
- Removed --single-process and --no-zygote; v37 uses a minimal Chromium configuration instead of experimental process-combining flags.
- Chromium flags are limited to no-sandbox, disable-setuid-sandbox, disable-dev-shm-usage, disable-gpu, disable-software-rasterizer, disable-extensions, no-first-run, and window-size.
- Updated whatsapp-web.js from 1.34.2 to 1.34.7 and Puppeteer from 24.0.0 to 24.38.0. The current whatsapp-web.js package publishes Puppeteer 24.38.0 as its dependency.
- No automatic initialization retry is used. This is intentional: retry loops can create multiple Chromium instances and exhaust cPanel process limits.
- Existing LocalAuth session is preserved.
- Queue locking, low-frequency polling, graceful shutdown, /qr, /health, /status and /send are retained.

Deployment check:
- After START, check /health first.
- Do not delete .wwebjs_auth.
- If has_qr becomes true, use /qr to scan.
