ci: migrate frontend workflow from npm to bun

- replace setup-node with oven-sh/setup-bun
- replace npm ci with bun install
- replace npm run with bun run
- fixes CI failure due to missing package-lock.json

Author: DevanshuNEU

.github/workflows/ci.yml

@@ -80,24 +80,22 @@ jobs:
     steps:
     - uses: actions/checkout@v4
 
-    - name: Set up Node.js
-      uses: actions/setup-node@v4
+    - name: Set up Bun
+      uses: oven-sh/setup-bun@v2
       with:
-        node-version: '20'
-        cache: 'npm'
-        cache-dependency-path: './frontend/package-lock.json'
+        bun-version: latest
 
     - name: Install dependencies
       working-directory: ./frontend
-      run: npm ci
+      run: bun install
 
     - name: Build frontend
       working-directory: ./frontend
-      run: npm run build
+      run: bun run build
 
     - name: Check TypeScript
       working-directory: ./frontend
-      run: npx tsc --noEmit
+      run: bun run tsc --noEmit
 
   security-scan:
     name: Security Scan