Polish UI components and rework AgentConfigForm

Major AgentConfigForm rework with improved adapter configuration
fields and layout. Refine sidebar, breadcrumbs, and card/tab
components for visual consistency. Clean up page layouts across
Activity, Agents, Approvals, Costs, Dashboard, Goals, Inbox,
Issues, Org, and Projects pages. Minor heartbeat-run CLI fix.

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

ui/src/components/MetricCard.tsx

@@ -13,7 +13,7 @@ export function MetricCard({ icon: Icon, value, label, description }: MetricCard
     <Card>
       <CardContent className="p-4">
         <div className="flex items-center gap-3">
-          <div className="rounded-md bg-muted p-2">
+          <div className="bg-muted p-2">
             <Icon className="h-4 w-4 text-muted-foreground" />
           </div>
           <div className="flex-1 min-w-0">