PackDetailView.copyValidationErrorsToClipboard() is an empty stub

[malpern]

Tier: 3 (minor polish)

From the pre-release feature-gap audit.

Problem

copyValidationErrorsToClipboard() in the Gallery pack-detail helpers is an empty placeholder; a working implementation already exists in the overlay path, so this is either dead code or an unfinished duplicate.

Evidence

• Sources/KeyPathAppKit/UI/Gallery/PackDetailView+Helpers.swift:78-80:

func copyValidationErrorsToClipboard() {
    // Placeholder for future implementation
}

• Working version: Sources/KeyPathAppKit/UI/Overlay/LiveKeyboardOverlayView.swift:311.

Suggested fix

Implement it (reuse the overlay version) or remove the stub.