feat: implement user authentication and dashboard

Adds a complete user authentication system and a protected dashboard.

- Implements JWT-based authentication using ElysiaJS.
- Integrates Prisma for database access and user management.
- Creates a login page and protected routes for the dashboard.
- Adds a dashboard layout with pages for API key management.
- Includes necessary UI components from Mantine.

src/server/lib/prisma.ts

@@ -0,0 +1,11 @@
+import { PrismaClient } from 'generated/prisma'
+
+const globalForPrisma = globalThis as unknown as {
+  prisma: PrismaClient | undefined
+}
+
+export const prisma = globalForPrisma.prisma ?? new PrismaClient()
+
+if (process.env.NODE_ENV !== 'production') {
+  globalForPrisma.prisma = prisma
+}