docs(18-02): complete scan-loop elevation plan

- 18-02-SUMMARY.md: elevation logic, DataGrid visual, 8 new tests
- STATE.md: position advanced, decisions recorded, session updated
- ROADMAP.md: phase 18 marked complete (2/2 summaries)
- REQUIREMENTS.md: OWN-02 marked complete

.planning/STATE.md

@@ -3,14 +3,14 @@ gsd_state_version: 1.0
 milestone: v2.3
 milestone_name: Tenant Management & Report Enhancements
 status: planning
-stopped_at: Completed 18-01-PLAN.md
-last_updated: "2026-04-09T12:25:36.302Z"
+stopped_at: Completed 18-02-PLAN.md
+last_updated: "2026-04-09T12:34:21.591Z"
 last_activity: 2026-04-09 — Roadmap created for v2.3 (phases 15-19)
 progress:
   total_phases: 5
-  completed_phases: 3
+  completed_phases: 4
   total_plans: 8
-  completed_plans: 7
+  completed_plans: 8
 ---
 
 # Project State
@@ -74,6 +74,8 @@ Decisions are logged in PROJECT.md Key Decisions table.
 - [Phase 18-auto-take-ownership]: OwnershipElevationService uses Tenant.SetSiteAdmin from PnP.Framework
 - [Phase 18-auto-take-ownership]: WasAutoElevated last positional param with default=false preserves all existing PermissionEntry callsites
 - [Phase 18-auto-take-ownership]: AutoTakeOwnership ViewModel setter uses fire-and-forget pattern matching DataFolder
+- [Phase 18-auto-take-ownership]: Toggle read before scan loop (not in exception filter) — await in when clause unsupported; pre-read bool preserves semantics
+- [Phase 18-auto-take-ownership]: WasAutoElevated DataTrigger last in RowStyle.Triggers — amber wins over RiskLevel color
 
 ### Pending Todos
 
@@ -85,7 +87,7 @@ None.
 
 ## Session Continuity
 
-Last session: 2026-04-09T12:25:29.455Z
-Stopped at: Completed 18-01-PLAN.md
+Last session: 2026-04-09T12:34:21.588Z
+Stopped at: Completed 18-02-PLAN.md
 Resume file: None
 Next step: `/gsd:plan-phase 15`