feat: 二维码访问功能，统一端点管道增强，端点迁移至 Services 层

- 新增二维码生成端点，自动检测局域网 IP，前端扫一扫即可打开网站
  - 提取 IApiResponse 接口，ServiceRequestBinder 支持强类型请求 DTO 绑定
  - FileStream 端点迁移至 AppEndpoints 统一注册，管道支持 FileStreamResponse 原始文件返回
  - 文件库端点全面使用 MapGet<TService, TRequest> 泛型注册
  - 移除 Avalonia-API/Extensions 中的业务端点文件，统一由 Services 层管理

Avalonia-Web-VUE/src/App.vue

@@ -21,6 +21,8 @@ const total = ref(0)
 const loading = ref(false)
 const scanningId = ref<number | null>(null)
 const errorMessage = ref('')
+const showQrCode = ref(false)
+const qrCodeData = ref<{ url: string; qrCodeBase64: string } | null>(null)
 
 const totalPages = computed(() => Math.max(1, Math.ceil(total.value / pageSize)))
 const availableRoots = computed(() => roots.value.filter((root) => root.isAvailable))
@@ -176,6 +178,15 @@ async function refreshAll() {
   await Promise.all([loadRoots(), loadFiles()])
 }
 
+async function loadQrCode() {
+  try {
+    qrCodeData.value = await api.qrCode()
+    showQrCode.value = true
+  } catch (error) {
+    setError(error)
+  }
+}
+
 onMounted(async () => {
   loading.value = true
   try {
@@ -320,6 +331,7 @@ onMounted(async () => {
       </div>
       <div class="mobile-header-actions">
         <button v-if="!isBrowsingRoots" type="button" class="back-button" @click="backToRoots">返回</button>
+        <button type="button" class="qr-button" title="生成二维码" @click="loadQrCode">二维码</button>
         <a href="/admin" class="admin-link">管理</a>
       </div>
     </header>
@@ -431,5 +443,17 @@ onMounted(async () => {
       <span>{{ page }} / {{ totalPages }}</span>
       <button type="button" :disabled="page >= totalPages" @click="changePage(page + 1)">下一页</button>
     </nav>
+
+    <Teleport to="body">
+      <div v-if="showQrCode" class="qr-overlay" @click.self="showQrCode = false">
+        <div class="qr-modal">
+          <h2>扫码访问</h2>
+          <img v-if="qrCodeData" :src="qrCodeData.qrCodeBase64" alt="QR Code" class="qr-image" />
+          <p v-else class="qr-hint">加载中...</p>
+          <p class="qr-hint">使用手机扫描二维码，即可在局域网中打开此网站</p>
+          <button type="button" class="primary-button qr-close" @click="showQrCode = false">关闭</button>
+        </div>
+      </div>
+    </Teleport>
   </main>
 </template>

Avalonia-Web-VUE/src/api/env.ts

@@ -1,10 +1,11 @@
 // 扩展 Window 接口，声明 C# 桥接注入的全局属性
 declare global {
-  interface Window {
+interface Window {
     /** 由 C# BridgeScript 注入，标记当前运行在 WebView2 环境中 */
     isWebView2?: boolean
     /** 由 WebView2 宿主注入，用于向 C# 发送消息 */
     invokeCSharpAction?: (message: string) => void
+    __pcMediaOrigin?: string
   }
 }
 

Avalonia-Web-VUE/src/api/http.ts

@@ -16,6 +16,9 @@ export const apiOrigin = (): string => HTTP_ORIGIN
 export const apiUrl = (path: string): string => {
   if (/^https?:\/\//i.test(path)) return path
   const normalized = path.startsWith('/') ? path : `/${path}`
+  if (isWebView2() && window.__pcMediaOrigin) {
+    return `${window.__pcMediaOrigin}${normalized}`
+  }
   return `${isWebView2() ? '' : HTTP_ORIGIN}${normalized}`
 }
 

Avalonia-Web-VUE/src/api/index.ts

@@ -90,4 +90,5 @@ export const api = {
   getTextPreview: (id: number) =>
     request<TextPreviewDto>(`files/text${qs({ id })}`),
   mediaUrl: (path: string) => apiUrl(path),
+  qrCode: () => request<{ url: string; qrCodeBase64: string }>('qrcode'),
 }

Avalonia-Web-VUE/src/assets/main.css

@@ -595,6 +595,59 @@ a {
   text-align: center;
 }
 
+.qr-button {
+  border-radius: 999px;
+  padding: 8px 14px;
+  color: var(--accent-strong);
+  background: #fff;
+}
+
+.qr-overlay {
+  position: fixed;
+  inset: 0;
+  z-index: 1000;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: rgba(16, 24, 40, 0.55);
+  backdrop-filter: blur(6px);
+}
+
+.qr-modal {
+  display: grid;
+  justify-items: center;
+  gap: 16px;
+  border-radius: 18px;
+  padding: 28px 24px 22px;
+  background: #fff;
+  box-shadow: 0 24px 60px rgba(16, 24, 40, 0.22);
+  text-align: center;
+}
+
+.qr-modal h2 {
+  margin: 0;
+  font-size: 20px;
+  font-weight: 800;
+}
+
+.qr-image {
+  display: block;
+  width: 240px;
+  height: 240px;
+  border: 1px solid var(--line);
+  border-radius: 12px;
+}
+
+.qr-hint {
+  margin: 0;
+  color: var(--muted);
+  font-size: 14px;
+}
+
+.qr-close {
+  min-width: 120px;
+}
+
 @media (max-width: 1100px) {
   .admin-layout,
   .admin-browser {