ci: disable scheduled SDK reference generation cron

Comment out the every-15-minutes schedule trigger. Generation still
runs on SDK release (repository_dispatch) and manual dispatch.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mishushakov

.github/workflows/sdk-reference-sync.yml

@@ -26,8 +26,10 @@ on:
 
   repository_dispatch:
     types: [sdk-release]
-  schedule:
-    - cron: "*/15 * * * *"
+  # Scheduled runs disabled — generation is triggered on SDK release (repository_dispatch)
+  # or manually (workflow_dispatch). Re-enable by uncommenting the schedule below.
+  # schedule:
+  #   - cron: "*/15 * * * *"
 
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   contents: write