Fix PR commenting workflow

Author: st0012

.github/workflows/pr-preview-comment.yml

@@ -1,9 +1,14 @@
 name: Comment on Fork PRs
 
 on:
-  pull_request:
+  pull_request_target:
     types: [opened, reopened, synchronize]
 
+# Required permissions for commenting on PRs
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
   comment-on-fork-pr:
     runs-on: ubuntu-latest
@@ -16,7 +21,6 @@ jobs:
           script: |-
             const prNumber = context.payload.pull_request.number;
             const workflowUrl = `https://github.com/ruby/rdoc/actions/workflows/cloudflare-preview.yml`;
-            const branch = context.payload.pull_request.head.ref;
             const commentMarker = "## Cloudflare Preview Deployment";
 
             // Create a direct link that pre-fills the PR number input
@@ -38,9 +42,9 @@ jobs:
             const messageLines = [
               `${commentMarker}`,
               `⚠️ This PR is from a fork, so the preview deployment workflow doesn't run automatically for security reasons.`,
-              `If you're a maintainer and want to preview this PR:`,
               ``,
-              `[➡️ Click here to run the workflow with PR #${prNumber} pre-filled](${dispatchUrl})`,
+              `### For Maintainers:`,
+              `[🚀 Click here to run the preview deployment workflow](${dispatchUrl})`,
               ``,
               `This will trigger a Cloudflare Pages preview deployment for this PR.`
             ];