feat(usage): add service health card with 7-day contribution grid

src/pages/UsagePage.tsx

@@ -27,6 +27,7 @@ import {
   CredentialStatsCard,
   TokenBreakdownChart,
   CostTrendChart,
+  ServiceHealthCard,
   useUsageData,
   useSparklines,
   useChartData
@@ -308,6 +309,9 @@ export function UsagePage() {
         onChange={handleChartLinesChange}
       />
 
+      {/* Service Health */}
+      <ServiceHealthCard usage={usage} loading={loading} />
+
       {/* Charts Grid */}
       <div className={styles.chartsGrid}>
         <UsageChart