fix cache error in build

.gitea/workflows/run-tests.yaml

@@ -42,11 +42,19 @@ jobs:
         uses: actions/setup-node@v4
         with:
           node-version: '18'
-          cache: 'npm'
-          cache-dependency-path: Development/server/package-lock.json
+
+      # Redirect the npm cache away from /root/.npm (root-owned on this runner)
+      # to a writable temp directory. Also clears any stale node_modules left
+      # by a previous run that the root-owned cache could not clean up.
+      - name: Fix npm cache permissions
+        run: |
+          mkdir -p /tmp/npm-cache
+          rm -rf node_modules || true
 
       - name: Install dependencies
-        run: npm ci --prefer-offline
+        env:
+          NPM_CONFIG_CACHE: /tmp/npm-cache
+        run: npm ci
 
       # Write a minimal env file so dotenv does not error on startup.
       # These tests do not hit the database; DB_* values are placeholders.