To update wasm-component-ld the process is (a) merge the PR here, (b) make a crates.io release from this repo, (c) update the wasm-component-ld source, (d) make a crates.io release of wasm-component-ld, and (e) update rust-lang/rust and wasi-sdk to the new versions. I'm able to help out with these parts too and it's fine to make a release for this.

Would you be up for adding a test here as well? For example something in crates/wit-component/tests/components I think would work. Something small is fine, but it'd be good to verify that everything works with a proposal like custom-page-sizes.