security: harden CI against supply-chain attacks (#20476)

- Pin all third-party actions to SHA
- Gate claude.yml triggers to internal authors with Harden-Runner egress
audit
- Ignore fork-PR lifecycle scripts
- Narrow cross-repo dispatch payloads
- Add 7d npm release-age gate
- Add CODEOWNERS on .github/** and .yarnrc.yml

---------

Co-authored-by: prastoin <paul@twenty.com>

.github/actions/deploy-twenty-app/action.yml

@@ -21,7 +21,7 @@ runs:
       run: corepack enable
 
     - name: Setup Node.js
-      uses: actions/setup-node@v4
+      uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
       with:
         node-version-file: '${{ inputs.app-path }}/.nvmrc'
         cache: yarn

.github/actions/install-twenty-app/action.yml

@@ -21,7 +21,7 @@ runs:
       run: corepack enable
 
     - name: Setup Node.js
-      uses: actions/setup-node@v4
+      uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
       with:
         node-version-file: '${{ inputs.app-path }}/.nvmrc'
         cache: yarn

.github/actions/nx-affected/action.yaml

@@ -20,7 +20,7 @@ runs:
       run: git fetch origin main --depth=1
     - name: Get last successful commit
       if: env.NX_BASE == ''
-      uses: nrwl/nx-set-shas@v4
+      uses: nrwl/nx-set-shas@3e9ad7370203c1e93d109be57f3b72eb0eb511b1 # v4
     - name: Fallback to origin/main if no base found
       if: env.NX_BASE == ''
       shell: bash

.github/actions/restore-cache/action.yaml

@@ -25,7 +25,7 @@ runs:
       run: |
         echo "CACHE_PRIMARY_KEY_PREFIX=v4-${CACHE_KEY}-${REF_NAME}" >> "${GITHUB_OUTPUT}"
     - name: Restore cache
-      uses: actions/cache/restore@v4
+      uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0 (restore)
       id: restore-cache
       with:
         key: ${{ steps.cache-primary-key-builder.outputs.CACHE_PRIMARY_KEY_PREFIX }}-${{ github.sha }}

.github/actions/save-cache/action.yaml

@@ -9,8 +9,11 @@ inputs:
 runs:
   using: "composite"
   steps:
+    # Fork PRs on pull_request already can't write to the base repo's cache (GitHub built-in).
+    # The fork guard is defense-in-depth for pull_request_target, which does have write access.
     - name: Save cache
-      uses: actions/cache/save@v4
+      if: ${{ format('{0}', github.event.pull_request.head.repo.fork) != 'true' }}
+      uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0 (save)
       with:
         key: ${{ inputs.key }}
         path: |

.github/actions/spawn-twenty-docker-image/action.yaml

@@ -48,7 +48,7 @@ runs:
         fi
 
     - name: Checkout docker compose files
-      uses: actions/checkout@v4
+      uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
       with:
         repository: ${{ inputs.twenty-repository }}
         ref: ${{ steps.resolve.outputs.git-ref }}

.github/actions/yarn-install/action.yaml

@@ -29,12 +29,12 @@ runs:
         echo "packages/*/node_modules" >> $GITHUB_OUTPUT
         echo 'EOF' >> $GITHUB_OUTPUT
     - name: Setup Node.js and get yarn cache
-      uses: actions/setup-node@v4
+      uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
       with:
         node-version: ${{ inputs.node-version }}
     - name: Restore node_modules
       id: cache-node-modules
-      uses: actions/cache/restore@v4
+      uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0 (restore)
       with:
         key: v4-${{ steps.globals.outputs.CACHE_KEY_PREFIX }}-${{github.sha}}
         restore-keys: v4-${{ steps.globals.outputs.CACHE_KEY_PREFIX }}-
@@ -44,10 +44,13 @@ runs:
       shell: ${{ steps.globals.outputs.ACTION_SHELL }}
       run: |
         yarn config set enableHardenedMode true
+        yarn config set enableScripts false
         yarn --immutable --check-cache
+    # Fork PRs on pull_request already can't write to the base repo's cache (GitHub built-in).
+    # The fork guard is defense-in-depth for pull_request_target, which does have write access.
     - name: Save cache
-      if: ${{ steps.cache-node-modules.outputs.cache-hit != 'true' && steps.cache-node-modules.outputs.cache-matched-key == '' }}
-      uses: actions/cache/save@v4
+      if: ${{ steps.cache-node-modules.outputs.cache-hit != 'true' && steps.cache-node-modules.outputs.cache-matched-key == '' && format('{0}', github.event.pull_request.head.repo.fork) != 'true' }}
+      uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0 (save)
       with:
         key: ${{ steps.cache-node-modules.outputs.cache-primary-key }}
         path: ${{ steps.globals.outputs.PATH_TO_CACHE }}