Summary

Create the backend-facing host adapter scaffolding required to plug Preview 3 draft packages into native, web, and node runtimes once the async component foundation is in place.

Parent tracking issue: #70
Suggested implementation order: 6 / 14

References

• https://github.com/WebAssembly/WASI/blob/main/docs/Preview2.md
• https://github.com/WebAssembly/component-model/blob/2e4800866d529aedc1b7730bc9452a4f85b97d8f/design/mvp/WIT.md
• https://github.com/WebAssembly/component-model/blob/2e4800866d529aedc1b7730bc9452a4f85b97d8f/design/mvp/Concurrency.md

Acceptance criteria

• Native and web backends expose a consistent Preview 3 draft host binding surface for later package issues to implement against.
• The node backend uses JS interop host adapters rather than node:wasi, which only targets Preview 1.
• Smoke coverage proves that the three backends can register Preview 3 draft host functions without regressing existing runtime setup.