Repo hygiene: fill stack-and-commands, normalize workplan statuses

- Fill .claude/rules/stack-and-commands.md (was an empty TODO template)
- Normalize workplan frontmatter statuses to canonical vocabulary
  (completed/done -> finished) per ADR-001
- Repair glued frontmatter delimiter in NK-WP-0001 (superseded_by line)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

workplans/NK-WP-0002-local-identity.md

@@ -3,7 +3,7 @@ id: NK-WP-0002
 type: workplan
 title: "Local Identity — Bootstrap User Store & Minimal OIDC"
 domain: infotech
-status: completed
+status: finished
 owner: worsch
 topic_slug: netkingdom
 state_hub_workstream_id: 7c9021b1-319c-4b4a-a8be-0642239a1893