[feature] Isolate `node:async_hooks` usage so it's not bundled when unused

[dinwwwh]

Problem or motivation

asyncStorageScope.ts imports node:async_hooks unconditionally:
https://github.com/HugoRCD/evlog/blob/main/packages/evlog/src/shared/asyncStorageScope.ts

This means the dependency gets pulled into the bundle even for consumers who don't use the async-storage-scope feature. In environments like Cloudflare Workers, this forces the nodejs_compat compatibility flag to be enabled, even when nothing in the app actually relies on it.

Proposed feature

Node-dependent features (like async_hooks) should be exported from a separate entry point, rather than bundled with the core package. This way, consumers who don't need those features aren't forced to pull in Node-specific dependencies or enable compatibility flags for runtimes that don't support them.

Possible implementation (optional)

No response

Alternatives you’ve considered (optional)

No response