Module versioning 

Skill version resolution

Implements deterministic version resolution with support for:

• default_version (stable, recommended for production)
• latest_version (opt-in, newest available)
• Lockfile-based pinning for reproducibility
• Fallback to manifest version field

Structs

ResolvedSkillRef

A fully resolved skill reference with concrete version

SkillLockfile

Lockfile for reproducible skill version resolution

Enums

SkillSource

Where a resolved skill comes from

Functions

resolve_default_version

Resolve version using default_version semantics (no version specified by user)

resolve_version

Resolve a skill version based on manifest, lockfile, and request