chore(ci): update PR preview workflows to clean up on close

.github/workflows/build-docs-preview.yml

@@ -3,7 +3,7 @@ name: Build Docs Preview
 on:
   pull_request:
     branches: [master]
-    types: [opened, synchronize, reopened]
+    types: [opened, synchronize, reopened, closed]
     paths:
       - 'content/**'
       - 'assets/**'
@@ -38,27 +38,32 @@ jobs:
       # plus objects.githubusercontent.com must be in allowed-endpoints or the
       # build dies at module resolution.
       - name: Harden Runner
+        if: github.event.action != 'closed'
         uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
         with:
           egress-policy: audit
 
       - name: Checkout PR
+        if: github.event.action != 'closed'
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
           submodules: recursive
 
       - name: Setup Go
+        if: github.event.action != 'closed'
         uses: actions/setup-go@b7ad1dad31e06c5925ef5d2fc7ad053ef454303e # v7.0.0
         with:
           go-version-file: go.mod
 
       - name: Setup Node
+        if: github.event.action != 'closed'
         uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: "22"
 
       - name: Install dependencies
+        if: github.event.action != 'closed'
         run: |
           if [ -f package-lock.json ] || [ -f npm-shrinkwrap.json ]; then
             npm ci
@@ -67,6 +72,7 @@ jobs:
           fi
 
       - name: Build PR preview
+        if: github.event.action != 'closed'
         env:
           HUGO_PREVIEW: "true"
           BASE_URL: /pr-preview/pr-${{ github.event.pull_request.number }}/

.github/workflows/deploy-docs-preview.yml

@@ -46,7 +46,7 @@ jobs:
         run: |
           ACTION=$(head -n1 temp-artifact/pr/action 2>/dev/null | tr -d '[:space:]')
           case "$ACTION" in
-            opened|reopened|synchronize) ;;
+            opened|reopened|synchronize|closed) ;;
             *) echo "::error::invalid or missing action: '$ACTION'"; exit 1 ;;
           esac
 
@@ -72,7 +72,7 @@ jobs:
           umbrella-dir: pr-preview
           pr-number: ${{ steps.meta.outputs.pr_number }}
           pages-base-url: docs.layer5.io
-          action: deploy
+          action: ${{ steps.meta.outputs.action == 'closed' && 'remove' || 'deploy' }}
           wait-for-pages-deployment: false
           comment: false
 
@@ -82,8 +82,9 @@ jobs:
           header: pr-preview
           number: ${{ steps.meta.outputs.pr_number }}
           message: |
-            🚀 Preview deployment: https://docs.layer5.io/pr-preview/pr-${{ steps.meta.outputs.pr_number }}/
-            > *Note: Preview may take a moment (GitHub Pages deployment in progress). Please wait and refresh. Track deployment [here](https://github.com/${{ github.repository }}/actions/workflows/pages/pages-build-deployment)*
+            ${{ steps.meta.outputs.action == 'closed' && 'Preview removed because the pull request was closed.'
+            || format('🚀 Preview deployment: https://docs.layer5.io/pr-preview/pr-{0}/
+            > *Note: Preview may take a moment (GitHub Pages deployment in progress). Please wait and refresh. Track deployment [here](https://github.com/{1}/actions/workflows/pages/pages-build-deployment)*', steps.meta.outputs.pr_number, github.repository) }}
 
   prune:
     # Both jobs push to gh-pages, but only prune retries a lost race, so deploy