fix: sync production DB schema for task detail API

Always run prisma db push on Render build and start so milestones/files columns exist for GET /tasks/:id.

backend/src/middleware/errorHandler.ts

@@ -22,5 +22,12 @@ export function errorHandler(
   }
 
   console.error('[Error]', err);
+
+  const prismaCode = (err as { code?: string }).code;
+  if (prismaCode === 'P2022') {
+    res.status(500).json({ message: 'DB 스키마가 최신이 아닙니다. 배포 후 다시 시도해 주세요.' });
+    return;
+  }
+
   res.status(500).json({ message: '서버 오류가 발생했습니다.' });
 }

backend/src/routes/tasks.ts

@@ -34,8 +34,9 @@ router.get('/', async (req, res, next) => {
 // GET /api/tasks/:id  — 단건 상세 조회
 router.get('/:id', async (req, res, next) => {
   try {
+    const taskId = String(req.params.id);
     const task = await prisma.task.findUnique({
-      where: { id: req.params.id },
+      where: { id: taskId },
       include: {
         assignee: { select: { id: true, name: true, department: true } },
         creator: { select: { id: true, name: true } },