Task Engineer

[hxuan190]

First, i saw module github.com/babilu-online/common is unavailable so i built a service context manually.
Second, i see the server will termianted immediately,that is not a best practice for handle shutdown server,so i implemented gracefull shutdown.
Third, i realize that when increase workload, this repo become difficult to maintain,so we need apply architecture and i choose Hexagonal for this, clean structure to easy maintain
Fourth, all service in this project is being used directly,that mean difficult to maintain code and violates the D principle in SOLID,so i used Dependency Injection between layers like transport,usecase,repository.make components become loose coupling. Init service by Constructor, make extension func