fix: array of type

refactor: expose client

fix: and logic condition

fix: add mutation fields

fix: method in umarshal error

fix: service imports

feat: New[Servce]Client and New[Service]Server

fix: echo examples

fix: flags before args

see: https://github.com/urfave/cli/blob/master/docs/migrate-v1-to-v2.md#flags-before-args

Create go.yml