Add github actions deployment workflow

Author: ajeetchaulagain

.github/workflows/deploy.yml

@@ -0,0 +1,50 @@
+name: Deploy CDK
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+    inputs:
+      deploy_branch:
+        description: 'Branch to deploy'
+        required: true
+        default: 'main'
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build application
+        run: npm run build
+
+      - name: Build Lambda layer
+        run: npm run build:layer
+
+      - name: Configure AWS credentials
+        uses: aws-actions/configure-aws-credentials@v4
+        with:
+          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          aws-region: ${{ secrets.AWS_REGION }}
+
+      - name: Install CDK dependencies
+        run: npm ci
+        working-directory: infra
+
+      - name: Deploy
+        run: npx cdk deploy --require-approval never
+        working-directory: infra