## What changed
- Move host skill discovery, snapshot caching, and configuration handling from
`codex-core-skills` to `codex-skills-extension`.
- Rename `SkillsService` and `SkillsLoadInput` to `HostSkillsService` and
`HostSkillsLoadInput` to distinguish the host implementation from other skill
providers.
- Keep shared loading primitives and skill outcome modeling in
`codex-core-skills`.
GitOrigin-RevId: d81a21791d2ef8c066e157e7e538b8cb7ee4c24b