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-product-brief-preview/bmad-manifest.json

@@ -0,0 +1,17 @@
+{
+  "module-code": "bmm",
+  "replaces-skill": "bmad-create-product-brief",
+  "capabilities": [
+    {
+      "name": "create-brief",
+      "menu-code": "CB",
+      "description": "Produces executive product brief and optional LLM distillate for PRD input.",
+      "supports-headless": true,
+      "phase-name": "1-analysis",
+      "after": ["brainstorming, perform-research"],
+      "before": ["create-prd"],
+      "is-required": true,
+      "output-location": "{planning_artifacts}"
+    }
+  ]
+}