gitproto: match CommandStatusErr by value so target-ref moves classify

[nodo]

Problem

ErrTargetRefMoved (PR #71, unreleased) never attaches on the real push path. asRefRejectedError and annotateLeaseFailure match go-git's CommandStatusErr with a pointer target:

var cs *packp.CommandStatusErr
if !errors.As(err, &cs) { return err }

but go-git returns CommandStatusErr by value from ReportStatus.Error() (value receiver Error(), constructed by value in report_status.go). errors.As against a **CommandStatusErr target never matches a value-typed CommandStatusErr in the chain, so:

• asRefRejectedError falls through → no *RefRejectedError, moved never set → errors.Is(err, ErrTargetRefMoved) is always false on a live receive-pack rejection.
• annotateLeaseFailure falls through → the lease-failure hint never fires.

Net effect: every concurrent target-ref rejection (remote ref has changed) passes through unclassified. The downstream mirror-pipeline worker that relies on errors.Is(err, ErrTargetRefMoved) to classify benign races sees nothing — the typed-rejection feature is inert in production.

The existing tests masked this by feeding &packp.CommandStatusErr{} (a pointer) as input, which the pointer target does match — but that is not how go-git hands the error over.

Fix

• Both functions now use a value errors.As target (var cs packp.CommandStatusErr), matching go-git's actual return type. go-git's own tests confirm a value target is correct (s.ErrorAs(rs.Error(), &CommandStatusErr{})).
• The table tests now build their input via go-git's real (&packp.CommandStatus{...}).Error() (value), and the underlying-error assertions use value targets.
• New TestAsRefRejectedError_RealReportStatusPath drives a real ReportStatus.Error() end to end through the production wrap — it fails on the pointer target and passes on the value target, so a pointer-vs-value relapse fails CI.

Verification

go test ./..., go vet, gofmt all clean. Confirmed the new test fails on the pre-fix pointer target and passes after.

Bug was in the unreleased typed-rejection feature (#71); never shipped in a tagged release.

🤖 Generated with Claude Code

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Note

Medium Risk
Changes error-classification on the push path (retry vs fatal behavior for embedders using ErrTargetRefMoved), but the fix restores intended unreleased behavior rather than altering semantics.

Overview
Fixes a bug where typed push rejections never activated on real receive-pack failures. annotateLeaseFailure and asRefRejectedError used a pointer errors.As target for go-git's packp.CommandStatusErr, but go-git returns that error by value from ReportStatus.Error() — so live ng statuses passed through unwrapped, errors.As to *RefRejectedError failed, and errors.Is(err, ErrTargetRefMoved) stayed false for concurrent CAS/lease rejections like remote ref has changed.

Both helpers now use a value errors.As target so lease hints and RefRejectedError / ErrTargetRefMoved classification work on the production path. Tests build inputs via CommandStatus.Error() (not hand-made pointers), and a new regression test drives a real ReportStatus.Error() through the wrap chain so a pointer-target relapse fails CI. CHANGELOG documents the fix and notes callers should use a value errors.As for the underlying CommandStatusErr.

^{Reviewed by Cursor Bugbot for commit 7d7406e. Configure here.}