[ISSUE] Add encoding to Content-Type

[quantummaiddeveloper]

Do you have an idea to improve the project? Please describe.
The response content type is set depending on the marshalling format. Additionally, it should
respect the provided output and set the encoding accordingly.

Is your feature request related to a problem? Please describe.
The encoding is necessary for clients to correctly display the response.

Describe the solution you'd like
If I return special characters, the response content type encoding should be set accordingly.