新增：连接管理、数据查询等功能

web/src/composables/useLocalStorage.ts

@@ -0,0 +1,34 @@
+/**
+ * LocalStorage composable
+ * 通用的 localStorage 操作
+ */
+
+import { watch, type Ref } from 'vue'
+
+export function useLocalStorage<T>(
+  key: string,
+  defaultValue: T,
+  storage: Storage = localStorage
+): [Ref<T>, (value: T) => void, () => void] {
+  const stored = storage.getItem(key)
+  const value = ref<T>(stored ? JSON.parse(stored) : defaultValue)
+
+  const setValue = (newValue: T) => {
+    value.value = newValue
+  }
+
+  const clearValue = () => {
+    value.value = defaultValue
+    storage.removeItem(key)
+  }
+
+  watch(value, (newValue) => {
+    try {
+      storage.setItem(key, JSON.stringify(newValue))
+    } catch (e) {
+      console.warn(`Failed to save ${key} to localStorage:`, e)
+    }
+  }, { deep: true })
+
+  return [value, setValue, clearValue]
+}