Change version parameter from str to VersionSpec in enable()/disable()
to support range-based version filtering.
- Add match_none parameter to VersionSpec.matches() for controlling
whether unversioned components match (defaults to True for backward
compatibility, False for enable/disable filtering)
- Update Enabled transform to use VersionSpec and call matches() with
match_none=False so unversioned components don't match version specs
- Update enable()/disable() signatures to accept VersionSpec
- Add comprehensive tests for version range matching
Examples:
- disable(version=VersionSpec(eq="v2")) - disable only v2
- disable(version=VersionSpec(gte="v2")) - disable v2 and later
- disable(version=VersionSpec(gte="v1", lt="v3")) - disable v1, v2
Rename Visibility to Enabled, collapse VisibilityRule into the transform,
and move enabled filtering from Provider to Server level so server-level
transforms can override provider-level disables.
