This PR merges the previous confusing features `serde` and `wasm` into a
single `serialize` feature.
We'll eventually do serialize + type information for both wasm and napi
targets.
`oxc_macros` is removed from `oxc_ast`'s dependency because it requires
`syn` and friends, which goes against our policy ["Third-party
dependencies should be
minimal."](https://oxc-project.github.io/docs/contribute/rules.html#development-policy)