feat: 添加 PWA 安装支持，包含安装提示和 iOS 指导页面

src/components/pwa-install-button/index.vue

@@ -0,0 +1,42 @@
+<script setup lang="ts">
+import { alertController, modalController } from "@ionic/vue";
+import IOSInstallGuide from "./ios-install-guide.vue";
+
+const { t } = useI18n();
+
+const {
+  showInstallButton,
+  promptInstall,
+  isIOS,
+} = usePWAInstall();
+
+async function handleInstall() {
+  const result = await promptInstall();
+
+  if (result.outcome === "accepted") {
+    const alert = await alertController.create({
+      header: t("pwa.install.success"),
+      message: t("pwa.install.successMessage"),
+      buttons: [t("common.ok")],
+    });
+    await alert.present();
+  }
+  else if (result.outcome === "ios-instruction") {
+    const modal = await modalController.create({
+      component: IOSInstallGuide,
+    });
+    await modal.present();
+  }
+}
+</script>
+
+<template>
+  <IonButton
+    v-if="showInstallButton"
+    expand="block"
+    @click="handleInstall"
+  >
+    <IIcBaselineDownload class="mr-2" />
+    {{ isIOS ? t('pwa.install.addToHomeScreen') : t('pwa.install.installApp') }}
+  </IonButton>
+</template>

src/components/pwa-install-button/ios-install-guide.vue

@@ -0,0 +1,48 @@
+<script setup lang="ts">
+import { modalController } from "@ionic/vue";
+
+const { t } = useI18n();
+
+function dismiss() {
+  modalController.dismiss();
+}
+</script>
+
+<template>
+  <IonPage>
+    <IonHeader>
+      <IonToolbar>
+        <IonTitle>{{ t('pwa.install.howToInstall') }}</IonTitle>
+        <IonButtons slot="end">
+          <IonButton @click="dismiss">
+            关闭
+          </IonButton>
+        </IonButtons>
+      </IonToolbar>
+    </IonHeader>
+    <IonContent class="ion-padding">
+      <div class="space-y-4">
+        <div class="text-center">
+          <IIcBaselineIosShare class="text-6xl text-primary mx-auto mb-4" />
+          <h2 class="text-lg font-semibold mb-2">
+            {{ t('pwa.install.iosTitle') }}
+          </h2>
+        </div>
+
+        <IonCard>
+          <IonCardContent>
+            <div class="space-y-3">
+              <p>{{ t('pwa.install.iosStep1') }}</p>
+              <p>{{ t('pwa.install.iosStep2') }}</p>
+              <p>{{ t('pwa.install.iosStep3') }}</p>
+            </div>
+          </IonCardContent>
+        </IonCard>
+
+        <div class="text-center text-sm text-gray-500">
+          {{ t('pwa.install.iosNote') }}
+        </div>
+      </div>
+    </IonContent>
+  </IonPage>
+</template>