✅ 1. Check Emulator Compatibility

You’re using:

"firebase-tools": "^14.24.1"
"firebase-functions": "6.6.0"

→ Problem: emulator support for firebase-functions v2 CloudEvent format was added only in v14.0.0+, and full support came later (~v15+).
Fix:
Upgrade Firebase CLI and dependencies:

npm install -g firebase-tools@latest
npm install firebase-functions@latest firebase-admin@latest

✅ 2. Ensure Emulator Uses Node.js 18 or 20

The Firebase Emulator does not yet fully support Node 22 runtime.
Your package.json says:

"engines": {
  "node": "22"
}

Fix:
Downgrade temporarily to a supported version for local testing:

"engines": {
  "node": "20"
}

Or use Node 20 in your local environment when emulating.

✅ 3. Keep Triggers in Separate Files (Optional but Safe)

Separate v1 and v2 triggers into different files to avoid cross-import issues:

// index.js
exports.authTriggers = require('./auth');
exports.firestoreTriggers = require('./firestore');

That avoids old v1 helpers accidentally mixing with v2 definitions.

✅ 4. Test on Real Cloud (if urgent)

If you need confirmation that it’s not your logic:

firebase deploy --only functions:onPrivateUserDataUpdateTrigger