Target prerelease branch for deployment testing

Temporarily deploy on merge to prerelease branch instead of main.
This allows testing the deploy workflow without requiring PR approval.

TODO: Switch back to main after testing is complete.
Signed-off-by: Marc Campbell <marc.e.campbell@gmail.com>

.github/workflows/deploy.yml

@@ -3,7 +3,8 @@ name: Deploy ttl.sh
 on:
   push:
     branches:
-      - main
+      - prerelease  # Temporary: deploy on prerelease for testing
+      # - main      # TODO: Switch back to main after testing
   workflow_dispatch:  # Manual trigger for emergencies
 
 concurrency: