feat: 添加用户设置功能，支持修改昵称和邮箱，重构相关路由和组件

src/views/user-settings/username.vue

@@ -0,0 +1,71 @@
+<script lang='ts' setup>
+import { toastController } from "@ionic/vue";
+import { arrowBackOutline } from "ionicons/icons";
+import { safeClient } from "@/api";
+import { authClient } from "@/auth";
+
+const { user } = useAuth();
+const username = ref(user.value?.username || "");
+const { updateProfile } = useUserStore();
+
+async function handleSave() {
+  if (!usernamePattern.test(username.value)) {
+    const toast = await toastController.create({
+      message: "用户名格式不正确",
+      duration: 2000,
+      position: "bottom",
+      color: "danger",
+    });
+    await toast.present();
+    return;
+  }
+  const { data } = await safeClient(authClient.updateUser({
+    username: username.value,
+  }));
+  if (data) {
+    updateProfile();
+    const toast = await toastController.create({
+      message: "用户名更新成功",
+      duration: 2000,
+      position: "bottom",
+      color: "success",
+    });
+    await toast.present();
+  }
+}
+</script>
+
+<template>
+  <ion-page>
+    <ion-header>
+      <ion-toolbar class="ui-toolbar">
+        <ion-buttons slot="start">
+          <ion-button @click="$router.back()">
+            <ion-icon slot="icon-only" :icon="arrowBackOutline" />
+          </ion-button>
+        </ion-buttons>
+        <ion-title>用户设置</ion-title>
+      </ion-toolbar>
+    </ion-header>
+
+    <ion-content :fullscreen="true" class="ion-padding">
+      <div class="space-y-3">
+        <ui-input
+          v-model="username"
+          placeholder="请输入用户名"
+          class="w-full"
+        />
+
+        <div class="text-xs text-gray-500">
+          仅支持字母、数字、下划线，长度 3-20 个字符
+        </div>
+
+        <ion-button expand="block" class="mt-5" @click="handleSave">
+          保存
+        </ion-button>
+      </div>
+    </ion-content>
+  </ion-page>
+</template>
+
+<style lang='css' scoped></style>