Archive closed workplans with completion-date prefixes

Moves the remaining finished workplans into workplans/archived/. Prefixes
use each workplan's own completion date per the convention, not the date
the archive sweep ran.

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

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 4609@bnt-lap001
Assistant-Session: 085df492-f02a-4fe6-acad-2aa52789fe1b

workplans/REUSE-WP-0008-graph-explorer.md

@@ -1,42 +0,0 @@
----
-id: REUSE-WP-0008
-type: workplan
-title: "Interactive relation graph explorer"
-domain: infotech
-repo: reuse-surface
-status: finished
-owner: codex
-topic_slug: helix-forge
-created: "2026-06-15"
-updated: "2026-06-15"
-state_hub_workstream_id: "63f8a2da-d179-4875-8cff-40a0fa2ca067"
----
-
-# Interactive relation graph explorer
-
-Close gap analysis priority 16. Provide a browsable HTML view of
-`docs/graph/capability-graph.mmd` for architects (UC-RS-016).
-
-## Add Graph Explorer Page
-
-```task
-id: REUSE-WP-0008-T01
-status: done
-priority: high
-state_hub_task_id: "2d08de47-d3c0-484f-a945-9691da9688e4"
-```
-
-Create `docs/graph/index.html` that renders the Mermaid graph in-browser with
-node labels and a legend for relation types.
-
-## Integrate Graph Generation
-
-```task
-id: REUSE-WP-0008-T02
-status: done
-priority: medium
-state_hub_task_id: "ada96492-88d0-438e-8d2b-ae0fdd8abb06"
-```
-
-Ensure `reuse-surface graph` documents and regenerates both `.mmd` and the
-explorer page dependency. Update `registry/README.md` and `AGENTS.md`.