feat: use gloo_utils for parsing

[NekoFluff]

This PR does two things:

1. Use JSValue::.into_serde() from gloo utils. I was having problems with the serde_wasm_bindgen::from_value. More specifically, I kept seeing: caught exception: SyntaxError: Unexpected token {
2. By adding Serialize to the Path enum, we can easily call move_by_path using the serialized/stringified version of the Path.

e.g.

creep.move_by_path(&JsValue::from_str(&path.to_string()))

[NekoFluff]

Close it, merge it, w/e you wish. I couldn't get serde_wasm_bindgen working locally so I just wanted to leave this here if anyone else encountered a similar issue.

[shanemadden]

Tried to reproduce this, and wasn't able to - can you provide any more info about how you're calling this that it's not working? I'm doing a simple test of find_path_to from one Position to another with a default callback and it's deserializing the returned result happily via serde-wasm-bindgen.

[NekoFluff]

Hmm interesting. I haven't played screeps in a hot second, but I can pull up my code and give it another whirl with the main branch this weekend to see if the issue still persists.