potential gh actions fix

.github/workflows/pr-checks.yml

@@ -19,8 +19,21 @@ jobs:
         with:
           node-version: '20'
 
+      - name: Install Yarn
+        run: corepack enable && corepack prepare [email protected] --activate # Specify the Yarn version you're using
+
+      - name: Cache Yarn dependencies
+        uses: actions/cache@v3
+        with:
+          path: |
+            .yarn/cache
+            node_modules
+          key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-yarn-
+
       - name: Install dependencies
-        run: yarn
+        run: yarn install --immutable --check-cache # Immutable mode to ensure lock file consistency
 
       - name: Run TypeScript, ESLint, and Prettier checks
         run: |