feat: F006 supply dashboard — complete spec implementation

- dataQualityService with getPortfolioQualitySummary()
- Service methods: getDashboardPropertiesSummary, getStrongMatches,
  getSignalSummary, getDashboardTasks added to respective services
- dashboardService uses Promise.allSettled for partial error resilience
- KpiCard: onClick + Tooltip support
- KpiGrid: navigate actions and tooltips per card
- StrongMatchMiniCard: Match Center, Prüfung, Vergleichen action buttons
- FutureSignalWidget: time horizon distribution (0–6, 6–12, 12–24 Mo.)
- SupplyDashboard: DashboardHeader, empty state, error state,
  partial widget errors, permission-based rendering per UserRole

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

src/components/supply/KpiCard.tsx

@@ -1,4 +1,4 @@
-import { Card, CardContent, Chip, Typography } from '@mui/material'
+import { Card, CardContent, CardActionArea, Chip, Tooltip, Typography } from '@mui/material'
 import type { KpiCardData } from '../../domain/dashboard'
 
 interface KpiCardProps {
@@ -9,32 +9,53 @@ export function KpiCard({ card }: KpiCardProps) {
   const trendColor =
     card.trend === 'up' ? 'success' : card.trend === 'down' ? 'error' : 'default'
 
-  return (
+  const content = (
+    <CardContent sx={{ p: 2.5 }}>
+      <Typography
+        variant="overline"
+        sx={{ color: 'text.secondary', lineHeight: 1.4, display: 'block' }}
+      >
+        {card.label}
+      </Typography>
+      <Typography variant="h4" sx={{ fontWeight: 700, mt: 0.5, mb: 0.5 }}>
+        {card.value}
+      </Typography>
+      {card.trendLabel && (
+        <Chip
+          label={card.trendLabel}
+          size="small"
+          color={trendColor as 'success' | 'error' | 'default'}
+          sx={{ mt: 0.5 }}
+        />
+      )}
+    </CardContent>
+  )
+
+  const card_ = (
     <Card
       sx={{
         borderTop: card.accent ? `4px solid ${card.accent}` : '4px solid transparent',
         height: '100%',
+        cursor: card.onClick ? 'pointer' : 'default',
       }}
     >
-      <CardContent sx={{ p: 2.5 }}>
-        <Typography
-          variant="overline"
-          sx={{ color: 'text.secondary', lineHeight: 1.4, display: 'block' }}
-        >
-          {card.label}
-        </Typography>
-        <Typography variant="h4" sx={{ fontWeight: 700, mt: 0.5, mb: 0.5 }}>
-          {card.value}
-        </Typography>
-        {card.trendLabel && (
-          <Chip
-            label={card.trendLabel}
-            size="small"
-            color={trendColor as 'success' | 'error' | 'default'}
-            sx={{ mt: 0.5 }}
-          />
-        )}
-      </CardContent>
+      {card.onClick ? (
+        <CardActionArea onClick={card.onClick} sx={{ height: '100%', alignItems: 'flex-start' }}>
+          {content}
+        </CardActionArea>
+      ) : (
+        content
+      )}
     </Card>
   )
+
+  if (card.tooltip) {
+    return (
+      <Tooltip title={card.tooltip} placement="top" arrow>
+        <span style={{ display: 'contents' }}>{card_}</span>
+      </Tooltip>
+    )
+  }
+
+  return card_
 }