fix: 预算执行KPI名称/维度为空 — deviation-report补kpi_name/dimension/unit字段

backend/app/api/budget.py

@@ -300,6 +300,10 @@ def get_deviation_report(
     rates = []
     for kpi in kpis:
         item = calc_period_deviation(db, kpi.id, period)
+        # 补充KPI基础信息（修复前端"预算执行KPI无名称"）
+        item["kpi_name"] = kpi.kpi_name
+        item["dimension"] = kpi.dimension
+        item["unit"] = kpi.unit or ""
         items.append(item)
         summary["total_kpis"] += 1