feat(dashboard): FlowPilot cockpit dashboard + sidebar redesign

- Replace QuickStartPage with FlowPilot-centric dashboard
- Add StartSessionInput with Guided/Chat mode toggle
- Add PendingEscalations, ActiveFlowPilotSessions, PerformanceCards
- Add KnowledgeBaseCards, TeamSummary, RecentFlowPilotSessions
- Every number/card is a portal to its detail page
- Restructure sidebar: Resolve/Knowledge/Insights sections
- Remove redundant nav items (FlowPilot, Flow Editor, Flow Assist, etc.)
- Wire prefill from dashboard input to FlowPilot intake
- Update mobile nav to match new sidebar structure

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

frontend/src/components/dashboard/PerformanceCards.tsx

@@ -0,0 +1,95 @@
+import { useState, useEffect } from 'react'
+import { useNavigate } from 'react-router-dom'
+import { CheckCircle, Clock, TrendingUp, Timer } from 'lucide-react'
+import type { LucideIcon } from 'lucide-react'
+import { sidebarApi } from '@/api'
+import { cn } from '@/lib/utils'
+
+interface StatCard {
+  label: string
+  value: string | number
+  icon: LucideIcon
+  iconColor: string
+  href: string
+  highlight?: boolean
+}
+
+export function PerformanceCards() {
+  const navigate = useNavigate()
+  const [resolved, setResolved] = useState(0)
+  const [active, setActive] = useState(0)
+  const [totalMinutes, setTotalMinutes] = useState(0)
+
+  useEffect(() => {
+    sidebarApi.getStats()
+      .then((stats) => {
+        setResolved(stats.resolved_today)
+        setActive(stats.active_count)
+        setTotalMinutes(stats.total_session_minutes_today)
+      })
+      .catch(() => {})
+  }, [])
+
+  const avgMttr = resolved > 0 ? Math.round(totalMinutes / resolved) : 0
+
+  const cards: StatCard[] = [
+    {
+      label: 'Resolved Today',
+      value: resolved,
+      icon: CheckCircle,
+      iconColor: '#34d399',
+      href: '/analytics',
+      highlight: true,
+    },
+    {
+      label: 'Avg Resolution',
+      value: avgMttr > 0 ? `${avgMttr}m` : '\u2014',
+      icon: Clock,
+      iconColor: '#22d3ee',
+      href: '/analytics',
+    },
+    {
+      label: 'Active Now',
+      value: active,
+      icon: TrendingUp,
+      iconColor: '#38bdf8',
+      href: '/sessions?filter=active',
+    },
+    {
+      label: 'Session Time',
+      value: totalMinutes > 0 ? `${totalMinutes}m` : '\u2014',
+      icon: Timer,
+      iconColor: '#fbbf24',
+      href: '/analytics',
+    },
+  ]
+
+  return (
+    <div className="grid grid-cols-2 sm:grid-cols-4 gap-3">
+      {cards.map((card, i) => (
+        <button
+          key={card.label}
+          onClick={() => navigate(card.href)}
+          className={cn(
+            'glass-card p-4 text-left fade-in',
+            i === 0 && 'active-glow'
+          )}
+          style={{ animationDelay: `${400 + i * 60}ms` }}
+        >
+          <div className="flex items-center justify-between mb-2">
+            <p className="font-label text-[0.5625rem] uppercase tracking-[0.1em] text-muted-foreground">
+              {card.label}
+            </p>
+            <card.icon size={14} style={{ color: card.iconColor }} />
+          </div>
+          <p className={cn(
+            'font-heading text-2xl font-extrabold tracking-tight',
+            card.highlight ? 'text-gradient-brand' : 'text-foreground'
+          )}>
+            {card.value}
+          </p>
+        </button>
+      ))}
+    </div>
+  )
+}