A script that checks a project's deployed Firestore rules against this repo #51

Every self-hoster of the cloud build runs their own Firebase project, and an app newer than its deployed firebase/firestore.rules fails in ways that look like unrelated bugs. Pairing breaking with "That code isn't active" is one we've already hit and fixed — the app was fine, the deployed rules were older than it.

There's currently no way to check short of eyeballing the Firebase console.

What to do

Add a small script under scripts/ that fetches the rules currently deployed to a project (the Firebase CLI can do this) and diffs them against firebase/firestore.rules, exiting non-zero with a readable diff when they differ. PowerShell or bash are both fine — match scripts/create-upload-keystore.ps1 if you like. Mention it in docs/SELF_HOSTING.md.

Done when

Running it against a project with stale rules prints what's missing and fails; against a current one it says so and exits 0.

Only relevant to cloud builds — a local build has no rules and no project.