Add fork-friendly PR preview deployment workflows

.github/workflows/docs-build.yml

@@ -0,0 +1,13 @@
+name: docs-build
+
+on:
+  pull_request: ~
+
+jobs:
+  preview:
+    uses: elastic/docs-builder/.github/workflows/preview-build.yml@main
+    with:
+      continue-on-error: true
+      strict: false
+    permissions:
+      contents: read

.github/workflows/docs-cleanup.yml

@@ -1,14 +1,14 @@
-name: docs
+name: docs-cleanup
 
 on:
   pull_request_target:
     types:
       - closed
 
 jobs:
-  docs-preview:
+  preview:
     uses: elastic/docs-builder/.github/workflows/preview-cleanup.yml@main
     permissions:
-      contents: read
+      contents: none
       id-token: write
       deployments: write

.github/workflows/docs-deploy.yml

@@ -0,0 +1,16 @@
+name: docs-deploy
+
+on:
+  workflow_run:
+    workflows: [docs-build]
+    types:
+      - completed
+
+jobs:
+  preview:
+    uses: elastic/docs-builder/.github/workflows/preview-deploy.yml@main
+    permissions:
+      contents: none
+      id-token: write
+      deployments: write
+      actions: read