feat: remove usernames

prisma/migrations/20260324215914_remove_usernames/migration.sql

@@ -0,0 +1,16 @@
+/*
+  Warnings:
+
+  - You are about to drop the column `username` on the `users` table. All the data in the column will be lost.
+  - You are about to drop the column `usernameUpdatedAt` on the `users` table. All the data in the column will be lost.
+
+*/
+-- DropIndex
+DROP INDEX "users_username_key";
+
+-- AlterTable
+ALTER TABLE "miis" ALTER COLUMN "allowedCopying" DROP NOT NULL;
+
+-- AlterTable
+ALTER TABLE "users" DROP COLUMN "username",
+DROP COLUMN "usernameUpdatedAt";

prisma/schema.prisma

@@ -9,7 +9,6 @@ datasource db {
 
 model User {
   id            Int       @id @default(autoincrement())
-  username      String?   @unique
   name          String
   email         String    @unique
   emailVerified DateTime?
@@ -19,8 +18,7 @@ model User {
   createdAt DateTime @default(now())
   updatedAt DateTime @updatedAt
 
-  usernameUpdatedAt DateTime?
-  imageUpdatedAt    DateTime?
+  imageUpdatedAt DateTime?
 
   accounts Account[]
   sessions Session[]