CI: reduce build memory to 2GB to prevent OOM on shared host

.gitea/workflows/ci.yml

@@ -22,8 +22,6 @@ jobs:
 
       - name: Install dependencies
         run: npm ci --legacy-peer-deps --ignore-scripts
-        env:
-          NODE_OPTIONS: "--max-old-space-size=4096"
 
       - name: Type check
         run: npx tsc --noEmit
@@ -37,7 +35,7 @@ jobs:
       - name: Build
         run: npx vite build
         env:
-          NODE_OPTIONS: "--max-old-space-size=4096"
+          NODE_OPTIONS: "--max-old-space-size=2048"
 
   deploy:
     if: ${{ github.ref == 'refs/heads/main' && github.event_name == 'push' }}