Validation errors are returned as `[object Object]`

Currently Elysia Eden turns all errors into string, if an error is an object value it will be turned into `[object Object]`

https://github.com/elysiajs/eden/blob/8a0f7b6194ea336b18a1c80d9a7dd6d2b1afbba2/src/errors.ts#L6