fix: only cache sharp output (#639)

Author: Strokkur424

.github/actions/setup-node-pnpm/action.yml

@@ -13,14 +13,8 @@ runs:
         cache: pnpm
         node-version: 22
 
-    - name: cache output directories
+    - name: cache sharp output
       uses: actions/cache@v4
       with:
-        path: |
-          .astro
-          .cache
-          dist
-          node_modules
-        key: ${{ runner.os }}-output-${{ hashFiles('**/pnpm-lock.yaml') }}
-        restore-keys: |
-          ${{ runner.os }}-output-
+        path: node_modules/.astro/assets
+        key: sharp