Normalize agent instructions and workplan frontmatter (STATE-WP-0067)

- Align agent files with on-disk workplan prefixes (infer from workplan ids)
- Set workplan domain to registered domain_slug; add topic_slug where applicable
- Repair frontmatter delimiter formatting; migrate legacy task status literals
- Regenerate AGENTS.md, CLAUDE.md, and .claude/rules from State Hub templates

workplans/CENG-WP-0001-intent-placeholder.md

@@ -2,7 +2,7 @@
 id: CENG-WP-0001
 type: workplan
 title: "Extract engine from citation-evidence umbrella"
-domain: citation_evidence
+domain: infotech
 repo: citation-engine
 status: done
 owner: codex

workplans/CENG-WP-0002-package-distribution.md

@@ -2,7 +2,7 @@
 id: CENG-WP-0002
 type: workplan
 title: "Package distribution — ADR-0002, publish readiness, contract sync"
-domain: citation_evidence
+domain: infotech
 repo: citation-engine
 status: done
 owner: codex