feat: implement Story 2.2 — Priority Alerts Panel with UI fixes

Add PriorityAlertsPanel component to the dashboard, update DashboardController
with alert logic, and apply misc UI fixes across sidebar, forms, and pages.
Includes epic-1 retrospective and sprint status update.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.claude/skills/bmad-create-architecture/architecture-decision-template.md

@@ -0,0 +1,12 @@
+---
+stepsCompleted: []
+inputDocuments: []
+workflowType: 'architecture'
+project_name: '{{project_name}}'
+user_name: '{{user_name}}'
+date: '{{date}}'
+---
+
+# Architecture Decision Document
+
+_This document builds collaboratively through step-by-step discovery. Sections are appended as we work through each architectural decision together._