Google Postmaster Tools returns NOT_FOUND for every domain add
Adding any domain to Postmaster Tools fails with a generic "Adding domain unsuccessful" toast.
No 4xx or 5xx to chase; the add call is a POST to `/batchexecute` which returns HTTP 200 with the error buried in the response body:
```rpcid MFo2Gb [5, null, [["type.googleapis.com/apps.postmaster.postbox.PostboxErrorInfo",[1]]]] 5 is gRPC NOT_FOUND. ```
"postbox" appears to be the internal service name.
Frontend build boq_gmail-postmaster-ui_20260816.04.
Ruled out:
- SPF/DKIM/MX all valid,
- site-verification ownership confirmed in Search Console, super admin,
- additional-services access On for all operating units, browsers, incognito and normal profiles. - - Fails identically for a domain I don't own, so it's account-scoped rather than domain-scoped.
Anyone else seeing this, or know what that error enum maps to?