ci: fix CI on fork PRs by moving off pull_request_target

.github/workflows/docs-deploy.yml

@@ -35,11 +35,22 @@ jobs:
       - name: 🔨 Build docs
         run: pnpm docs:build
 
+      # Fork PRs receive no repository secrets, so CLOUDFLARE_API_TOKEN is empty
+      # and the deploy is a guaranteed failure. Skip it for them — the docs
+      # BUILD above still runs, which is the part that can actually regress.
+      # The `push` arm is required: pushes to main have no pull_request context.
       - name: 📥 Install Wrangler
+        if: github.event_name == 'push' ||
+          github.event.pull_request.head.repo.full_name == github.repository
         run: npm install -g wrangler
 
       - name: 🚀 Deploy to Cloudflare Pages
-        run: wrangler pages deploy apps/docs/.vitepress/dist --project-name=shelf-docs --branch=${{ github.event_name == 'push' && 'main' || github.head_ref }}
+        if: github.event_name == 'push' ||
+          github.event.pull_request.head.repo.full_name == github.repository
         env:
           CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_API_TOKEN }}
           CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          # github.head_ref is attacker-controlled PR input (a branch name), so
+          # it goes through env instead of being interpolated into the script.
+          DEPLOY_BRANCH: ${{ github.event_name == 'push' && 'main' || github.head_ref }}
+        run: wrangler pages deploy apps/docs/.vitepress/dist --project-name=shelf-docs --branch="$DEPLOY_BRANCH"

.github/workflows/react-doctor.yml

@@ -8,7 +8,7 @@ name: 🩺 React Doctor
 #   2. Fails the check if NEW errors are introduced — warnings stay advisory.
 
 on:
-  pull_request_target:
+  pull_request:
     paths:
       - "apps/webapp/**/*.ts"
       - "apps/webapp/**/*.tsx"
@@ -20,17 +20,12 @@ on:
       - ".github/workflows/react-doctor.yml"
       - ".github/scripts/react-doctor-pr-comment.mjs"
 
-jobs:
-  authorize:
-    environment: ${{ github.event_name == 'pull_request_target' &&
-      github.event.pull_request.head.repo.full_name != github.repository &&
-      'external' || '' }}
-    runs-on: ubuntu-latest
-    steps:
-      - run: echo ✓
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
 
+jobs:
   doctor:
-    needs: authorize
     name: 🩺 React Doctor (${{ matrix.app.name }})
     runs-on: ubuntu-latest
     permissions:
@@ -47,17 +42,19 @@ jobs:
           - name: companion
             dir: apps/companion
     steps:
-      - name: 🛑 Cancel previous runs
-        uses: styfle/cancel-workflow-action@0.11.0
-
-      - name: ⬇️ Checkout PR head
+      - name: ⬇️ Checkout PR merge ref
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.pull_request.head.sha || github.ref }}
+          # No `ref:` — the default checkout resolves to the PR merge ref and is
+          # exempt from actions/checkout's fork-PR guard. fetch-depth: 0 is
+          # still required so `origin/<base>` exists for the --diff below.
           fetch-depth: 0
+          # Nothing after this step needs git auth, so the token never lands in
+          # .git/config where fork-controlled code could read it back out.
+          persist-credentials: false
 
       - name: 🪢 Re-attach HEAD to a named branch
-        # actions/checkout leaves us on a DETACHED HEAD when given a sha.
+        # actions/checkout leaves us on a DETACHED HEAD at the PR merge ref.
         # react-doctor's --diff path calls `git rev-parse --abbrev-ref HEAD`
         # to find the current branch; in detached state that returns the
         # literal "HEAD", which the CLI interprets as "no branch" and silently
@@ -157,14 +154,33 @@ jobs:
           cat "$RUNNER_TEMP/comment.md"
 
       - name: 💬 Post or update PR comment
+        # Fork and Dependabot PRs run with a read-only GITHUB_TOKEN, so the
+        # comment API 403s for them. Those PRs surface findings through the
+        # inline annotations (emitted as log commands, which need no token) and
+        # the job summary written below.
+        #
+        # Predicate on pull_request.user.login, NOT github.actor: the read-only
+        # token is keyed to who AUTHORED the PR, but github.actor becomes the
+        # re-runner's login on a manual re-run — which would wrongly re-enable
+        # this step on a Dependabot PR re-run.
         if: always() && steps.changes.outputs.changed == 'true'
+          && github.event.pull_request.head.repo.full_name == github.repository
+          && github.event.pull_request.user.login != 'dependabot[bot]'
+        # Backstop for any read-only-token case not enumerated above.
+        continue-on-error: true
         uses: marocchino/sticky-pull-request-comment@v2
         with:
           # Per-app header so the two matrix jobs maintain separate sticky
           # comments instead of overwriting each other.
           header: react-doctor-${{ matrix.app.name }}
           path: ${{ runner.temp }}/comment.md
 
+      - name: 📋 Write findings to job summary
+        # Runs for EVERY PR including forks and Dependabot — this is the only
+        # aggregated report those PRs get, since the sticky comment is skipped.
+        if: always() && steps.changes.outputs.changed == 'true'
+        run: cat "$RUNNER_TEMP/comment.md" >> "$GITHUB_STEP_SUMMARY"
+
       - name: ❌ Fail if errors introduced
         if: steps.changes.outputs.changed == 'true' && steps.doctor.outputs.exit_code != '0'
         run: |

.github/workflows/test.yml

@@ -1,7 +1,25 @@
-name: 🧪 Test PR from fork
+name: 🧪 Test
+
+# SECURITY INVARIANT — read this before adding a job to this workflow.
+#
+# This workflow runs on `pull_request`, so fork PRs execute here. GitHub gives
+# those runs a read-only GITHUB_TOKEN and NO repository secrets — that is
+# precisely what makes it safe to run untrusted contributor code automatically.
+#
+# Therefore: any job that consumes a secret MUST NOT live in this workflow.
+# Secret-bearing jobs (e.g. the Playwright/E2E suite below) belong in a separate
+# workflow gated behind the `external` environment, and must never check out
+# fork PR code in that trusted context.
+#
+# Do NOT "fix" a fork PR checkout failure by setting `allow-unsafe-pr-checkout:
+# true` on a checkout step. That re-enables the "pwn request" attack class that
+# actions/checkout began blocking in July 2026.
 
 on:
-  pull_request_target:
+  pull_request:
+  # Called by deploy.yml on pushes to main/dev. The secrets below are declared
+  # for the E2E job that currently lives commented-out at the bottom of this
+  # file; deploy.yml passes all six, so this block must not be removed.
   workflow_call:
     secrets:
       SESSION_SECRET:
@@ -17,28 +35,32 @@ on:
       DATABASE_URL:
         required: true
 
-jobs:
-  authorize:
-    environment: ${{ github.event_name == 'pull_request_target' &&
-      github.event.pull_request.head.repo.full_name != github.repository &&
-      'external' || '' }}
+# Least privilege, pinned explicitly. The repo default is already `read`, but
+# pinning it means a future org-level default change cannot silently escalate
+# these jobs. `contents: read` is what actions/checkout needs to fetch.
+permissions:
+  contents: read
 
-    runs-on: ubuntu-latest
-    steps:
-      - run: echo ✓
+concurrency:
+  # PR number for PR runs; run_id on the workflow_call path so a push to main
+  # gets a unique group and can never be cancelled by a PR run. Note that in a
+  # reusable workflow the `github` context belongs to the CALLER.
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}
+  cancel-in-progress: true
 
+jobs:
   lint:
-    needs: authorize
     name: ⬣ ESLint
     runs-on: ubuntu-latest
     steps:
-      - name: 🛑 Cancel Previous Runs
-        uses: styfle/cancel-workflow-action@0.11.0
-
       - name: ⬇️ Checkout repo
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.pull_request.head.sha || github.ref }}
+          # No `ref:` — the default checkout resolves to the PR merge ref and is
+          # exempt from actions/checkout's fork-PR guard. No credentials
+          # persisted: nothing after this step needs git auth, so the token
+          # never lands in .git/config where fork code could read it.
+          persist-credentials: false
 
       - name: 📦 Setup pnpm
         uses: pnpm/action-setup@v4
@@ -55,17 +77,13 @@ jobs:
         run: pnpm run lint
 
   typecheck:
-    needs: authorize
     name: ʦ TypeScript
     runs-on: ubuntu-latest
     steps:
-      - name: 🛑 Cancel Previous Runs
-        uses: styfle/cancel-workflow-action@0.11.0
-
       - name: ⬇️ Checkout repo
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.pull_request.head.sha || github.ref }}
+          persist-credentials: false
 
       - name: 📦 Setup pnpm
         uses: pnpm/action-setup@v4
@@ -82,17 +100,13 @@ jobs:
         run: pnpm run typecheck
 
   vitest:
-    needs: authorize
     name: ⚡ Vitest
     runs-on: ubuntu-latest
     steps:
-      - name: 🛑 Cancel Previous Runs
-        uses: styfle/cancel-workflow-action@0.11.0
-
       - name: ⬇️ Checkout repo
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.pull_request.head.sha || github.ref }}
+          persist-credentials: false
 
       - name: 📦 Setup pnpm
         uses: pnpm/action-setup@v4
@@ -111,19 +125,16 @@ jobs:
       - name: ⚡ Run vitest
         run: pnpm --filter @shelf/webapp test -- --run
 
+  # NOTE: this job consumes secrets — see the SECURITY INVARIANT at the top of
+  # this file. Do NOT re-enable it here. It belongs in its own workflow gated
+  # behind the `external` environment, and must not check out fork PR code.
   # playwright:
-  #   needs: authorize
   #   name: 🎭 Playwright
   #   timeout-minutes: 60
   #   runs-on: ubuntu-latest
   #   steps:
-  #     - name: 🛑 Cancel Previous Runs
-  #       uses: styfle/cancel-workflow-action@0.11.0
-
   #     - name: ⬇️ Checkout repo
-  #       uses: actions/checkout@v3
-  #       with:
-  #         ref: ${{ github.event.pull_request.head.sha || github.ref }}
+  #       uses: actions/checkout@v4
 
   #     - name: 🔑 Make envfile
   #       uses: SpicyPizza/create-envfile@v2.0
@@ -137,9 +148,9 @@ jobs:
   #         file_name: .env
 
   #     - name: ⎔ Setup node
-  #       uses: actions/setup-node@v3
+  #       uses: actions/setup-node@v4
   #       with:
-  #         node-version: 18
+  #         node-version: 22
 
   #     - name: 📥 Download deps
   #       uses: bahmutov/npm-install@v1
@@ -153,7 +164,7 @@ jobs:
   #     - name: Run Playwright tests
   #       run: npx playwright test
 
-  #     - uses: actions/upload-artifact@v3
+  #     - uses: actions/upload-artifact@v4
   #       if: always()
   #       with:
   #         name: playwright-report