feat(dashboard): optimize dashboard layout and add new charts

app/api/routes/proxies.py

@@ -108,3 +108,21 @@ async def batch_delete(
 async def clean_invalid(service: ProxyService = Depends(get_proxy_service)):
     count = await service.clean_invalid()
     return success_response(f"清理了 {count} 个无效代理", {"deleted_count": count})
+
+
+@router.get("/latency-distribution")
+async def get_latency_distribution(
+    service: ProxyService = Depends(get_proxy_service),
+):
+    """获取延迟分布数据，用于直方图展示"""
+    distribution = await service.get_latency_distribution()
+    return success_response("获取延迟分布成功", distribution)
+
+
+@router.get("/score-distribution")
+async def get_score_distribution(
+    service: ProxyService = Depends(get_proxy_service),
+):
+    """获取评分分布数据，用于柱状图展示"""
+    distribution = await service.get_score_distribution()
+    return success_response("获取评分分布成功", distribution)