docs(openspec): add SDD artifact trail for recent alarm and EQ changes

Persist the exploration, proposal, spec, design, tasks, and
verify/archive reports produced during the multi-device EQ,
alarm-countdown, and notification-visual-polish SDD cycles.

openspec/changes/multi-device-eq/state.yaml

@@ -0,0 +1,21 @@
+change: multi-device-eq
+status: archived
+archived_at: "2026-06-27T00:00:00Z"
+archived_location: "openspec/changes/archive/2026-06-27-multi-device-eq/"
+verdict: PASS WITH WARNINGS
+test_results:
+  total_tests: 184
+  passing: 184
+  critical_issues: 0
+analyzer_issues: 0
+warnings:
+  - "W-1: Section toggle visible when feature OFF (correct intended behavior)"
+  - "W-2: API shape difference (reads via cargar() not standalone getters) — no impact"
+artifacts:
+  proposal_id: 2185
+  spec_id: 2186
+  design_id: 2187
+  tasks_id: 2188
+  apply_progress_id: 2189
+  verify_report_id: 2192
+  archive_report_id: 2193