feat: Add wasm module build

[timfish]

This PR:

• Adds serde and wasm features so that consumers of the Rust library don't need to bring in all those dependencies if they don't need them
• Adds a transform function to InstrumentationVisitor - this was moved from the test utils with unwrap() removed
• Adds annotations to the config types which creates conversion code between rust<->javascript and typescript types
• Adds a wasm module in the library that is only enabled with the wasm feature
• In the wasm module, add functions and types that are exposed from wasm via #[wasm_bindgen]
• InstrumentationVisitor lifetimes had to be removed because they're not supported across rust<->js boundary
• Adds a package.json

You can npm install && npm run build to build the module.
You can run npm test to run a single JavaScript test of the wasm and asserts the output matches what's expected.

[jsumners-nr]

Looks good to me.