feat(store): 添加tabbar模块并导出

新增tabbar状态管理模块，包含tabbar项的状态、getters和actions
在store统一导出文件中添加tabbar模块的导出

src/store/index.ts

@@ -15,3 +15,4 @@ export default store
 
 // 模块统一导出
 export * from './user'
+export * from './tabbar'

src/store/tabbar.ts

@@ -0,0 +1,48 @@
+import { defineStore } from 'pinia'
+
+export interface TabbarItem {
+  name: string
+  value: number | null
+  active: boolean
+}
+
+export const useTabbarStore = defineStore('tabbar', {
+  state: (): { tabbarItems: TabbarItem[] } => ({
+    tabbarItems: [
+      { name: 'index', value: null, active: true },
+      { name: 'about', value: null, active: false },
+    ],
+  }),
+  getters: {
+    getTabbarItems: (state) => {
+      return state.tabbarItems
+    },
+    getActive: (state) => {
+      const item = state.tabbarItems.find((item) => item.active)
+      return item || state.tabbarItems[0]
+    },
+    getTabbarItemValue: (state) => {
+      return (name: string) => {
+        const item = state.tabbarItems.find((item) => item.name === name)
+        return item && item.value ? item.value : null
+      }
+    },
+  },
+  actions: {
+    setTabbarItem(name: string, value: number) {
+      const tabbarItem = this.tabbarItems.find((item) => item.name === name)
+      if (tabbarItem) {
+        tabbarItem.value = value
+      }
+    },
+    setTabbarItemActive(name: string) {
+      this.tabbarItems.forEach((item) => {
+        if (item.name === name) {
+          item.active = true
+        } else {
+          item.active = false
+        }
+      })
+    },
+  },
+})