chore: complete v1.2 milestone — archive and tag

Archive v1.2 Modularization & Polish milestone:
- Archive ROADMAP.md, REQUIREMENTS.md, and audit to milestones/
- Evolve PROJECT.md with v1.2 validated requirements and decisions
- Reorganize ROADMAP.md with collapsed milestone groupings
- Delete REQUIREMENTS.md (fresh for next milestone)
- Update STATE.md and MILESTONES.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.planning/STATE.md

@@ -2,11 +2,16 @@
 
 ## Current Position
 
-- **Milestone:** v1.2 -- Modularization & Polish
-- **Phase:** 13 of 13 (Documentation Overhaul)
-- **Plan:** 1 of 1 complete
-- **Status:** Phase 13 COMPLETE (README overhaul, documentation consolidation)
-- **Last activity:** 2026-02-08 -- Completed 13-01 (README architecture/config/troubleshooting, removed outdated DEPLOYMENT_GUIDE.md)
+- **Milestone:** v1.2 SHIPPED
+- **Status:** Milestone archived, tagged v1.2
+- **Last activity:** 2026-02-08 -- v1.2 milestone completed and archived
+
+## Project Reference
+
+See: .planning/PROJECT.md (updated 2026-02-08)
+
+**Core value:** When you get a container update notification or notice a service is down, you can immediately investigate and act from your phone.
+**Current focus:** Planning next milestone
 
 ## Progress
 
@@ -14,7 +19,7 @@
 v1.0: [**********] 100% SHIPPED
 v1.1: [**********] 100% SHIPPED
 
-v1.2: [**********] 100% COMPLETE
+v1.2: [**********] 100% SHIPPED
 
 Phase 10:   Workflow Modularization         [**********] 100% COMPLETE (+ 10-07 UAT fixes)
 Phase 10.1: Aggressive Modularization       [**********] 100% COMPLETE (9/9 plans + UAT closure)