fix wrong parametre working dir and add cache dependency

.github/workflows/build.yml

@@ -38,10 +38,10 @@ jobs:
         run: quasar build
           
       - name: Set up Go
-        working-directory: ./backend
         uses: actions/setup-go@v5
         with:
           go-version: '1.24.0'
+          cache-dependency-path: backend/go.sum
 
       - name: Set up Git credentials for private modules
         run: |
@@ -49,16 +49,6 @@ jobs:
         env:
           GH_PAT_FOR_MODULES: ${{ secrets.GH_PAT }}
 
-      - name: Restore Go module cache
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/go/pkg/mod
-            ~/.cache/go-build # Optional, but good for build cache
-          key: ${{ runner.os }}-${{ matrix.goos }}-${{ matrix.goarch }}-go-${{ hashFiles('backend/go.sum') }}
-          restore-keys: |
-            ${{ runner.os }}-${{ matrix.goos }}-${{ matrix.goarch }}-go-
-
       - name: Go Mod Tidy & Download
         working-directory: ./backend
         run: go mod tidy -v