add refresh tokens migration

apps/backend/src/migrations/2025-08-17_14-54-18_add_refresh_token.ts

@@ -0,0 +1,33 @@
+import { Kysely, sql } from 'kysely';
+
+export async function up(db: Kysely<unknown>): Promise<void> {
+  await db.schema
+    .createTable('refresh_tokens')
+    .addColumn('id', 'bigserial', (col) => col.primaryKey())
+    .addColumn('user_id', 'bigserial', (col) => col.notNull())
+    .addForeignKeyConstraint(
+      'fk_user_id_refresh_tokens_users',
+      ['user_id'],
+      'users',
+      ['id'],
+      (col) => col.onDelete('cascade'),
+    )
+    .addColumn('token', 'text', (col) => col.notNull())
+    .addUniqueConstraint('uniq_user_id_tokens_refresh_tokens', [
+      'user_id',
+      'token',
+    ])
+    .addColumn('valid_until', 'timestamptz', (col) => col.notNull())
+    .addColumn('created_at', 'timestamptz', (col) =>
+      col.notNull().defaultTo(sql`now()`),
+    )
+    .addColumn('updated_at', 'timestamptz', (col) =>
+      col.notNull().defaultTo(sql`now()`),
+    )
+    .addColumn('deleted_at', 'timestamptz')
+    .execute();
+}
+
+export async function down(db: Kysely<unknown>): Promise<void> {
+  await db.schema.dropTable('refresh_tokens').execute();
+}