fix: 修复后台管理分析图表渲染失败及 Chart.js 导入兼容性问题

src/lib/components/admin/AnalyticsPanel.svelte

@@ -28,7 +28,6 @@
 						totalBytes += day.sum.bytes;
 					});
 					hitRate = totalRequests > 0 ? (totalCached / totalRequests) * 100 : 0;
-					renderChart(data);
 				}
 				loading = false;
 			})
@@ -39,11 +38,17 @@
 			});
 	});
 
+	$effect(() => {
+		if (chartCanvas && analyticsData && analyticsData.length > 0) {
+			renderChart(analyticsData);
+		}
+	});
+
 	async function renderChart(data: any[]) {
 		if (!chartCanvas) return;
 
 		const ChartJS = await import('chart.js/auto');
-		const Chart = ChartJS.default;
+		const Chart = ChartJS.default || ChartJS;
 
 		const labels = data.map((d: any) => d.dimensions.date);
 		const requests = data.map((d: any) => d.sum.requests);