more preview fixes, workflow_run is way too hard to use

.github/workflows/build.yaml

@@ -23,4 +23,4 @@ jobs:
           path: ./dist
           overwrite: true
           retention-days: 1
-          name: build-artifacts-${{ github.event.number }}
+          name: build-artifacts-${{ github.run_id }}

.github/workflows/preview.yaml

@@ -4,6 +4,7 @@ on:
   workflow_run:
     workflows: ["build"]
     types:
+      - requested
       - completed
 
 permissions:
@@ -12,24 +13,43 @@ permissions:
 
 jobs:
   preview:
-    #if: ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event == 'pull_request' }}
+    if: ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event == 'pull_request' }}
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+
       - name: Download build artifacts
         uses: actions/download-artifact@v4
         with:
-          name: build-artifacts-${{ github.event.number }}
+          name: build-artifacts-${{ github.event.workflow_run.id }}
           path: ./dist
           run-id: ${{ github.event.workflow_run.id }}
           github-token: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Find PR number
+        id: pr
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const response = await github.rest.search.issuesAndPullRequests({
+              q: 'repo:${{ github.repository }} is:pr sha:${{ github.event.workflow_run.head_sha }}',
+              per_page: 1,
+            })
+            const items = response.data.items
+            if (items.length < 1) {
+              console.error('No PRs found')
+              return
+            }
+            const pullRequestNumber = items[0].number
+            console.info("Pull request number is", pullRequestNumber)
+            return pullRequestNumber
+
       # deploy
       - name: Deploy to Cloudflare Pages
         id: cloudflare-publish
         uses: cloudflare/pages-action@v1.5.0
         with:
-          branch: ${{ github.event.number }}
+          branch: ${{ steps.pr.outputs.result }}
           projectName: connect
           accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
           apiToken: ${{ secrets.CLOUDFLARE_PAGES_TOKEN }}
@@ -45,5 +65,7 @@ jobs:
             * mark your PR as a draft until it's ready to review
             * post the preview on [Discord](https://discord.comma.ai); feedback from users will speedup the PR review
 
-            deployed preview: https://${{ github.event.number }}.connect-d5y.pages.dev
+            deployed preview: https://${{ steps.pr.outputs.result }}.connect-d5y.pages.dev
           comment_tag: run_id
+          pr_number: ${{ steps.pr.outputs.result }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}