feat: create a banner with custom text by admin

packages/prisma/migrations/20240222183156_display_banner/migration.sql

@@ -0,0 +1,12 @@
+-- CreateTable
+CREATE TABLE "Banner" (
+    "id" SERIAL NOT NULL,
+    "text" TEXT NOT NULL,
+    "customHTML" TEXT NOT NULL,
+    "userId" INTEGER,
+
+    CONSTRAINT "Banner_pkey" PRIMARY KEY ("id")
+);
+
+-- AddForeignKey
+ALTER TABLE "Banner" ADD CONSTRAINT "Banner_userId_fkey" FOREIGN KEY ("userId") REFERENCES "User"("id") ON DELETE SET NULL ON UPDATE CASCADE;