Enabled echo_response for all methods + serde(rename_all = "snake_case")

[acelot]

Summary

• echo_response: true for all stream_api methods
• serde(rename_all = "snake_case")

Related Issues
No related issues.

Proposed Changes

• Enabled echo_response for all stream_api methods. I don't know why it was disabled, it makes PacketRouter useless for methods like update_config, update_user, etc
• Changed serde(rename_all = "camelCase") attribute to serde(rename_all = "snake_case") in build.rs. Same situation, I don't know why camelCase was used here. Protobuf protos are using snake_case field names, so I think we should use the same. This change will allow us to use static field names for referencing, for example using nameof crate.

Checklist

• Tests pass locally (I've tested config saving)
• Nothing to change in documentation

[acelot]

@lukipuki Hi, could you please review?

[lukipuki]

Thanks for the contribution!