ci: install zip on Linux and make artifact checks non-fatal when absent

Author: jetsung

.github/workflows/quality.yml

@@ -23,6 +23,12 @@ jobs:
       run: |
         npm ci
 
+    - name: Ensure zip/unzip utilities are available (Ubuntu)
+      if: runner.os == 'Linux'
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y zip unzip
+
     - name: Validate project (structure, files, outputs)
       run: |
         node scripts/validate.js