[Feature] Signup

[Nitiwat-owen]

• implement signup service and handler

• write unit test for signup service and handler

• introduce gomock for mocking interface

  mockGen:
      mockgen -source ./src/pkg/service/auth/auth.service.go -destination ./src/mocks/service/auth/auth.mock.go
      mockgen -source ./src/pkg/service/user/user.service.go -destination ./src/mocks/service/user/user.mock.go
      mockgen -source ./src/app/validator/validator.go -destination ./src/mocks/validator/validator.mock.go
      mockgen -source ./src/app/router/context.go -destination ./src/mocks/router/context.mock.go
  

Demo

• Signup successfully:
  
  

• Signup failed due to duplicate email:
  

[bookpanda]

LGTM