PyScript <py-config> packages: offline wheel resolution missing

Goal: create a fully repeatable PyScript development environment that works without network access by pinning the PyScript runtime and declaring required pure‑Python packages in a <py-config> block.

Constraint: micropip, which resolves the packages list, can only fetch wheels from PyPI and requires an active connection; the current documentation does not describe an offline wheel cache, lockfile, or vendor directory that would allow the same package set to be installed in an air‑gapped setting.

Uncertainty: whether PyScript can be directed to a local directory of pre‑downloaded wheels or to use a lockfile to guarantee identical versions when offline.

• Does PyScript support specifying a local wheel directory or path for micropip to resolve packages?
• Can a lockfile (e.g., requirements.txt with exact hashes) be supplied to <py-config> to pin versions for offline install?
• Is there a documented method to pre‑cache or vendor wheels during a build step so that <py-config> can operate without network?