Look into using Rust Codebase to generate the DTOs

[MV-GH]

Possible avenues:

• Something crude that goes over the AST and generates KT DTOs
• Find a tool to convert rust DTOs to OpenAPI, then another tool to convert OpenAPI to KT DTOs
• Make ts_rs equivalent for KT

Find a tool to convert rust DTOs to OpenAPI is also needed for lemmy_openapi_spec