feat: chuẩn bị backend cho tính năng anonymous user upload ảnh không cần đăng nhập

backend/prisma/migrations/20260619014336_feat_anonymous_users/migration.sql

@@ -0,0 +1,15 @@
+-- DropForeignKey
+ALTER TABLE "Photo" DROP CONSTRAINT "Photo_tourId_fkey";
+
+-- AlterTable
+ALTER TABLE "Photo" ADD COLUMN     "originalUrl" TEXT,
+ALTER COLUMN "tourId" DROP NOT NULL,
+ALTER COLUMN "imageUrl" DROP NOT NULL;
+
+-- AlterTable
+ALTER TABLE "User" ADD COLUMN     "isAnonymous" BOOLEAN NOT NULL DEFAULT false,
+ALTER COLUMN "email" DROP NOT NULL,
+ALTER COLUMN "passwordHash" DROP NOT NULL;
+
+-- AddForeignKey
+ALTER TABLE "Photo" ADD CONSTRAINT "Photo_tourId_fkey" FOREIGN KEY ("tourId") REFERENCES "Tour"("id") ON DELETE SET NULL ON UPDATE CASCADE;