upload final_results.json artifact (#642)

Upload `final_results.json` as an artifact that docs can download, process, and publish

Author: shorgi

.github/workflows/test-all.yaml

@@ -8,6 +8,7 @@ on:
       - 'packages/**'
       - '!**/README.md'
   workflow_call:
+  workflow_dispatch:
 
 jobs:
   build-matrix:
@@ -93,6 +94,12 @@ jobs:
           name: results.md
           path: ./results.md
           retention-days: 7
+      - name: Upload final JSON results
+        uses: actions/upload-artifact@v4
+        with:
+          name: final_results.json
+          path: ./final_results.json
+          retention-days: 28    
 
   pr-info:
     if: ${{ github.event_name == 'pull_request' }}