feat: 移除所有访客模式提示和入口，保持界面极简

- 删除登录页访客模式进入按钮
- 删除 MachineList 访客提示样式
- 访客界面无任何说明文字，只展示机器列表
- 登录页仅提供管理员登录入口

web/src/views/Login.vue

@@ -26,9 +26,6 @@
           </div>
         </el-form-item>
         <el-button type="primary" size="large" class="login-btn" :loading="loading" :icon="Connection" @click="login">登录</el-button>
-        <div class="login-guest">
-          <el-button text size="small" :icon="View" @click="guestLogin">访客模式进入</el-button>
-        </div>
       </el-form>
     </div>
     <div class="login-footer">
@@ -40,8 +37,8 @@
 <script setup>
 import { ref } from 'vue'
 import { useRouter } from 'vue-router'
-import { User, Lock, Connection, View } from '@element-plus/icons-vue'
-import { login as apiLogin, guestLogin as apiGuest } from '@/api'
+import { User, Lock, Connection } from '@element-plus/icons-vue'
+import { login as apiLogin } from '@/api'
 import { setAuth } from '@/router'
 import { ElMessage } from 'element-plus'
 
@@ -63,17 +60,6 @@ async function login() {
   } catch (e) {}
   loading.value = false
 }
-
-async function guestLogin() {
-  loading.value = true
-  try {
-    const res = await apiGuest()
-    setAuth(res.data)
-    ElMessage.success('已进入访客模式')
-    router.push('/')
-  } catch (e) {}
-  loading.value = false
-}
 </script>
 
 <style scoped>
@@ -173,16 +159,6 @@ async function guestLogin() {
   letter-spacing: 0.5px;
   margin-top: 6px;
 }
-.login-guest {
-  text-align: center;
-  margin-top: 14px;
-}
-.login-guest :deep(.el-button) {
-  color: var(--text-muted);
-}
-.login-guest :deep(.el-button:hover) {
-  color: var(--text-secondary);
-}
 
 .login-footer {
   margin-top: 24px;

web/src/views/MachineList.vue

@@ -427,22 +427,6 @@ function formatTime(t) {
 </script>
 
 <style scoped>
-.guest-page-notice {
-  padding: 10px 16px;
-  background: rgba(242, 201, 76, 0.12);
-  border: 1px solid rgba(242, 201, 76, 0.3);
-  border-radius: 8px;
-  margin-bottom: 16px;
-  display: flex;
-  align-items: center;
-  gap: 8px;
-  font-size: 13px;
-  color: #d29922;
-}
-.guest-page-notice .el-icon {
-  font-size: 16px;
-}
-
 .toolbar {
   display: flex;
   align-items: center;