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.

types/env.d.ts

@@ -0,0 +1,8 @@
+declare namespace NodeJS {
+  interface ProcessEnv {
+    DATABASE_URL?: string;
+    JWT_SECRET?: string;
+    BUN_PUBLIC_BASE_URL?: string;
+    PORT?: string;
+  }
+}