docs: record owner-requested Gitea Actions disablement

docs/BUILDING.md

@@ -108,8 +108,10 @@ signing/notarization requires Apple tooling and credentials. See the
 
 ## CI and packaging gates
 
-GitHub and Gitea workflows define native OS matrices. Gitea requires registered
-runners matching its configured labels. A workflow declaration does not prove
+Gitea Actions are disabled for this repository at the owner's request after
+repeated failure emails (2026-10-12). Existing workflows remain as references:
+GitHub defines native OS matrices; Gitea targets its available Ubuntu runner.
+A workflow declaration does not prove
 a platform was tested; Linux/macOS gates remain open until actual job evidence
 exists. Current workflow checks do not certify the separately built Google
 worker or execute downloaded-model tests automatically.