setup ci workflow, test folder, and mock-test

.github/workflows/ci.yml

@@ -0,0 +1,32 @@
+name: Client CI
+
+on:
+  push:
+    branches:
+      - dev
+    paths:
+      - 'client/**'
+
+  workflow_dispatch:    
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
+      - name: Install dependencies
+        run: |
+          cd client
+          npm install
+
+      - name: Run tests
+        run: |
+          cd client
+          npm test

client/.eslintrc.cjs

@@ -1,6 +1,6 @@
 module.exports = {
   root: true,
-  env: { browser: true, es2020: true },
+  env: { browser: true, es2020: true, jest: true },
   extends: [
     'eslint:recommended',
     'plugin:@typescript-eslint/recommended',