[FLI-772] Rust Client Side SDK

[markphelps]

Language

Rust 🦀

FFI Support

• I've validated that the language supports Foreign Function Interface (FFI) bindings

Additional Context

I dont think we'll need to go through FFI since our engine is written in Rust

Willing to Implement

• I'm willing to help implement the Flipt Client SDK in this language if it's accepted. 🙌

Willing to Review

• I'm willing to review contributions to the Flipt Client SDK in this language if it's accepted.

Additional Notes

No response

_FLI-772