feat(ci): trigger preview release on master push (#425)

This allows pkg.pr.new packages to be published when commits are merged
to master, not just for pull requests.

This enables consumers to use the latest master branch packages via
pkg.pr.new without waiting for an official npm release.

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## Summary by CodeRabbit

* **Chores**
* Updated CI/CD workflow configuration to enhance deployment automation.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>

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Author: TriPSs

.github/workflows/publish-preview.yml

@@ -2,6 +2,9 @@ name: Publish Preview
 
 on:
   pull_request:
+  push:
+    branches:
+      - master
   workflow_dispatch:
 
 env: