fix(backend): Downgrade cors for fastify 4 compat and enable auto-seeding

backend/prisma/seed.ts

@@ -1,4 +1,5 @@
 import { PrismaClient, RoomType, SectionType } from '@prisma/client';
+import * as bcrypt from 'bcrypt';
 
 const prisma = new PrismaClient();
 
@@ -56,7 +57,7 @@ async function main() {
         await prisma.user.create({
             data: {
                 email: ownerEmail,
-                passwordHash: 'password123',
+                passwordHash: await bcrypt.hash('password123', 10),
                 name: 'Travis',
                 role: 'OWNER', // Enum fallback
                 roleId: ownerRole?.id,