feat: add PostgreSQL database support and development scripts

- Added pg and @types/pg dependencies for PostgreSQL integration
- Created database testing and backend initialization scripts
- Changed dev server port to 3002 to avoid conflicts

src/app/api/packages/[id]/route.ts

@@ -0,0 +1,75 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { PackageService } from '@/services/packageService'
+
+export async function GET(
+  request: NextRequest,
+  { params }: { params: { id: string } }
+) {
+  try {
+    const packageData = await PackageService.getById(params.id)
+    
+    if (!packageData) {
+      return NextResponse.json(
+        { error: 'Package not found' },
+        { status: 404 }
+      )
+    }
+
+    return NextResponse.json(packageData)
+  } catch (error) {
+    console.error('Error fetching package:', error)
+    return NextResponse.json(
+      { error: 'Failed to fetch package' },
+      { status: 500 }
+    )
+  }
+}
+
+export async function PUT(
+  request: NextRequest,
+  { params }: { params: { id: string } }
+) {
+  try {
+    const body = await request.json()
+    const packageData = await PackageService.update(params.id, body)
+    
+    if (!packageData) {
+      return NextResponse.json(
+        { error: 'Package not found' },
+        { status: 404 }
+      )
+    }
+
+    return NextResponse.json(packageData)
+  } catch (error) {
+    console.error('Error updating package:', error)
+    return NextResponse.json(
+      { error: 'Failed to update package' },
+      { status: 500 }
+    )
+  }
+}
+
+export async function DELETE(
+  request: NextRequest,
+  { params }: { params: { id: string } }
+) {
+  try {
+    const success = await PackageService.delete(params.id)
+    
+    if (!success) {
+      return NextResponse.json(
+        { error: 'Package not found' },
+        { status: 404 }
+      )
+    }
+
+    return NextResponse.json({ success: true })
+  } catch (error) {
+    console.error('Error deleting package:', error)
+    return NextResponse.json(
+      { error: 'Failed to delete package' },
+      { status: 500 }
+    )
+  }
+}