fix(ios-prebuild): stage deps headers in compose-xcframework + sort test imports

Two CI fixes for the prebuild-ios-core workflow:

- prebuild-ios-core.yml: the compose-xcframework job downloaded the
  build slices and React headers but never staged
  third-party/ReactNativeDependencies.xcframework. buildReactNativeHeadersXcframework
  folds the third-party deps namespaces (folly/glog/boost/...) into
  ReactNativeHeaders.xcframework, so it fail-closed with "deps namespace
  'folly' missing ... refusing to ship an incomplete
  ReactNativeHeaders.xcframework". Add the Download + Extract
  ReactNativeDependencies steps (mirroring build-slices) so the deps
  headers are present before composing.

- headers-spec-test.js: reorder requires so the `../headers-spec` import
  sorts before `fs`, fixing the @react-native/monorepo/sort-imports
  warning that failed `eslint --max-warnings 0` in test_js.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: chrfalch

.github/workflows/prebuild-ios-core.yml

@@ -157,6 +157,22 @@ jobs:
           pattern: prebuild-ios-core-headers-${{ matrix.flavor }}-*
           path: packages/react-native/.build/headers
           merge-multiple: true
+      - name: Download ReactNativeDependencies
+        if: steps.restore-ios-xcframework.outputs.cache-hit != 'true'
+        uses: actions/download-artifact@v7
+        with:
+          name: ReactNativeDependencies${{ matrix.flavor }}.xcframework.tar.gz
+          path: /tmp/third-party/
+      - name: Extract ReactNativeDependencies
+        if: steps.restore-ios-xcframework.outputs.cache-hit != 'true'
+        shell: bash
+        run: |
+          # ReactNativeHeaders.xcframework (built by the compose step) folds in
+          # the third-party deps namespaces (folly/glog/boost/...), so the deps
+          # headers must be staged here too — not just in build-slices.
+          tar -xzf /tmp/third-party/ReactNativeDependencies${{ matrix.flavor }}.xcframework.tar.gz -C /tmp/third-party/
+          mkdir -p packages/react-native/third-party/
+          mv /tmp/third-party/packages/react-native/third-party/ReactNativeDependencies.xcframework packages/react-native/third-party/ReactNativeDependencies.xcframework
       - name: Setup Keychain
         if: ${{ steps.restore-ios-xcframework.outputs.cache-hit != 'true' && env.REACT_ORG_CODE_SIGNING_P12_CERT != '' }}
         uses: apple-actions/import-codesign-certs@v3 # https://github.com/marketplace/actions/import-code-signing-certificates

packages/react-native/scripts/ios-prebuild/__tests__/headers-spec-test.js

@@ -10,12 +10,12 @@
 
 'use strict';
 
-const fs = require('fs');
 const {
   planFromInventory,
   renderNamespaceModuleMap,
   renderReactModuleMap,
 } = require('../headers-spec');
+const fs = require('fs');
 
 // isUmbrellaSafe reads each header's source to reject extern-inline defs. Stub
 // it to empty so synthetic objc-modular-candidate headers count as umbrella-safe