fix: resolve file download error

- content-type이 text/html 일 경우에만 에러 핸들링, 이외 타입은 octet-stream으로 반환

src/app/api/qna/file/route.ts

@@ -4,6 +4,7 @@ import { NextResponse } from 'next/server'
 export async function GET(request: Request) {
   const { searchParams } = new URL(request.url)
   const encodeFileNo = searchParams.get('encodeFileNo')
+
   const srcFileNm = searchParams.get('srcFileNm')
 
   if (!encodeFileNo) {
@@ -16,17 +17,16 @@ export async function GET(request: Request) {
         encodeFileNo,
       },
     })
-    if (response.headers['content-type'] === 'application/octet-stream;charset=UTF-8') {
+    if (response.headers['content-type'] === 'text/html;charset=utf-8') {
-      return new NextResponse(response.data, {
-        status: 200,
-        headers: {
-          'Content-Type': 'application/octet-stream;charset=UTF-8',
-          'Content-Disposition': `attachment; filename="${srcFileNm}"`,
-        },
-      })
-    } else {
       return NextResponse.json({ error: 'file not found' }, { status: 404 })
     }
+    return new NextResponse(response.data, {
+      status: 200,
+      headers: {
+        'Content-Type': 'application/octet-stream;charset=UTF-8',
+        'Content-Disposition': `attachment; filename="${srcFileNm}"`,
+      },
+    })
   } catch (error: any) {
     return NextResponse.json({ error: error.response.data }, { status: 500 })
   }