* fix: remove StatusOpts, MergeOpts, CheckoutOpts — no call sites

No function in the package accepts any of these three types, and nothing constructs one anywhere: Checkout.Status() takes zero arguments, Repo.Merge takes positional string arguments, and CheckoutOpts had no construction site at all. A public type with no call site documents a capability that does not exist -- a consumer reading MergeOpts{Strategy: ...} in the docs could reasonably conclude a strategy-selecting merge API exists; it never did.

Repo.Merge and Checkout.Status keep their current signatures. An options-struct refactor for Merge was considered and declined.

CheckoutOpts.Force was also a third same-named Force field in this package, alongside the already-removed UpdateOpts.Force (#58) and the real, fully-wired ExtractOpts.Force -- removing it also removes that readability hazard. ExtractOpts.Force and its plumbing (checkout.go Extract -> internal/checkout.ExtractOpts -> extract.go's Force check) are untouched.

* docs: match em dash style in CHANGELOG breaking-change bullet

The new StatusOpts/MergeOpts/CheckoutOpts entry used ASCII double hyphens where the adjacent CloneOpts and UpdateOpts.Force bullets in the same file use a real em dash. check-in: 1a33f22119 user: [email protected] tags: trunk