Allow functions to override /sitemap.xml for data-driven apps

Base44's auto-generated /sitemap.xml only includes statically defined page files. It has no awareness of dynamic routes populated from entity data — so any app with database-driven public pages is invisible to Google at scale.

My use case

3dprintsbyvic.com has ~1,400 public filament detail pages at /filaments/{brand-slug}/{filament-slug}, all generated from Filament and Brand entity records. The auto-generated sitemap lists 10 URLs. The other ~1,390 never get discovered by Google.

What I tried

I built a generateSitemap function that produces a valid 1,061-URL sitemap (anonymous fetch, HTTP 200, correct Content-Type). But /functions/* URLs are served with X-Robots-Tag: noindex, which Google respects absolutely — so submitting the function URL to Search Console returns "URL is not available to Google / Excluded by 'noindex' tag."

Confirmed with Tamir in support: there's currently no way to override /sitemap.xml or opt out of the noindex header on a specific function.

What would solve it (any one of these)

1. Allow a function to be registered as the handler for /sitemap.xml

2. Allow opting out of X-Robots-Tag: noindex on specific functions

3. Allow scheduled functions to write files to public/ at runtime

Why this matters beyond me

Every Base44 app with dynamic content has this problem — product catalogs, blog CMS, user profile directories, directory sites, any app where URLs are generated from entity records. At scale it makes Base44 a poor choice for SEO-dependent apps, because Google can only discover the handful of static page shells.

Happy to beta-test whatever shape the solution takes.