chore(spec): record isTenancyDisabled in the API-surface snapshot

The check:api-surface CI gate flags any public-API delta; the new
export from #3249 is intentional (see the accompanying changeset).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017YcGcBgUxeeKXXxv189kqR

Author: claude

packages/spec/api-surface.json

@@ -508,6 +508,7 @@
     "isDateMacroToken (function)",
     "isFilterAST (function)",
     "isIncoherentAggregate (function)",
+    "isTenancyDisabled (function)",
     "isTitleEligible (function)",
     "missingFieldValues (function)",
     "objectForm (const)",