feat: 月报统计（总）;查询的月报数据自动保存

lib/db.js

@@ -31,3 +31,19 @@ export function getPanelData(uid) {
 export function savePanelData(uid, data) {
   setDB('panel', uid, data);
 }
+
+/**
+ * @param {string} uid
+ * @returns {Array<object>}
+ */
+export function getMonthlyData(uid) {
+  return getDB('monthly', uid) || [];
+}
+
+/**
+ * @param {string} uid
+ * @param {Array<object>} data
+ */
+export function saveMonthlyData(uid, data) {
+  setDB('monthly', uid, data);
+}