chore: disable automatic release workflow until NPM_TOKEN is configured

The release workflow fails on every push to main because there's no
NPM_TOKEN secret configured. Switch to manual trigger (workflow_dispatch)
until npm publishing credentials are set up.

Re-enable by uncommenting the push trigger and adding NPM_TOKEN secret.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/release.yml

@@ -1,8 +1,9 @@
 name: Release
 
 on:
-  push:
-    branches: [main]
+  workflow_dispatch: # Manual trigger only until NPM_TOKEN is configured
+  # push:
+  #   branches: [main]
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}