refactor(turbopack): Use `ResolvedVc` for `turbopack-ecmascript` (#72564)
### What?
Use `ResolvedVc` for struct fields in `turbopack-ecmascript` crate
### Why?
Follow-up of https://github.com/vercel/next.js/pull/72200,
https://github.com/vercel/next.js/pull/72382,
https://github.com/vercel/next.js/pull/72320
### How?
Closes PACK-3438
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Co-authored-by: Benjamin Woodruff <benjamin.woodruff@vercel.com>