pr-status, pr-create, pr-commits, pr-merge, pr-reviews,
pr-assign-reviewer, issue-create, issue-edit, and diff existed only to
refuse via renamed() and name their namespaced replacement. Zero live
callers remain (docs/, /knowledge/, scripts/ checked), so drop the
enum variants, their dispatch arms, and the now-unused renamed()
helper in one change.
The kind-agnostic flat aliases (view, comment, comments, assign,
close, labels, timeline) are untouched: each has no single scoped
replacement, since it works on either an issue or a PR without
knowing which.
Refs #3974
83595663bb