fix(config): 🔧 update code style scrip

update code style script to only check for added and modified files only, and apply lint check

Ref: #19

.github/workflows/pr-guardrails.yml

@@ -148,7 +148,7 @@ jobs:
         id: git_diff
         run: |
           echo Searching for files added/changed in ${{ github.event.pull_request.head.ref }}, since the last commit in ${{ github.event.pull_request.base.ref }}
-          echo "FILES_TO_LINT=$(git diff --name-only --diff-filter=AM --recursive ${{ github.event.pull_request.head.sha }}..${{ github.event.pull_request.base.sha }} ./app/*.{js,jsx,ts,tsx} | xargs)" >> $GITHUB_OUTPUT
+          echo "FILES_TO_LINT=$(git diff --name-only --diff-filter=AM --recursive ${{ github.event.pull_request.head.sha }}..${{ github.event.pull_request.base.sha }} ./service/*.{js,jsx,ts,tsx} | xargs)" >> $GITHUB_OUTPUT
 
       - name: Run ESLint for service
         run: |