refactor: 优化预约系统代码结构并改进日期处理

- 移除packages.php中的会话检查，改为统一入口控制
- 在index.php中优化日期初始化逻辑并添加默认日期选择
- 重构bookings.php的查询逻辑，关联套餐表并改进时间显示格式

bookings.php

@@ -20,7 +20,7 @@ if (isset($_POST['action']) && isset($_POST['booking_id'])) {
 
 // 获取所有预约
 try {
-    $stmt = $pdo->query("SELECT * FROM bookings ORDER BY appointment_date DESC, appointment_time DESC");
+    $stmt = $pdo->query("SELECT b.*, p.package_name FROM bookings b LEFT JOIN packages p ON b.package_id = p.id ORDER BY b.start_time DESC");
     $bookings = $stmt->fetchAll();
 } catch (Exception $e) {
     $error_message = '获取预约列表失败：' . $e->getMessage();
@@ -95,13 +95,13 @@ try {
                                 <strong>车牌号：</strong><?php echo htmlspecialchars($booking['car_number']); ?>
                             </div>
                             <div>
-                                <strong>服务类型：</strong><?php echo htmlspecialchars($booking['service_type']); ?>
+                                <strong>服务套餐：</strong><?php echo htmlspecialchars($booking['package_name'] ?? '未选择套餐'); ?>
                             </div>
                             <div>
-                                <strong>预约日期：</strong><?php echo $booking['appointment_date']; ?>
+                                <strong>预约日期：</strong><?php echo date('Y-m-d', strtotime($booking['start_time'])); ?>
                             </div>
                             <div>
-                                <strong>预约时间：</strong><?php echo $booking['appointment_time']; ?>
+                                <strong>预约时间：</strong><?php echo date('H:i', strtotime($booking['start_time'])); ?> - <?php echo date('H:i', strtotime($booking['end_time'])); ?>
                             </div>
                         </div>
 

index.php

@@ -306,8 +306,12 @@ $packages_json = json_encode(array_map(function($package) {
         document.addEventListener('DOMContentLoaded', function() {
             const today = new Date();
             today.setDate(today.getDate());
-            document.getElementById('appointment_date').value = today.toISOString().split('T')[0];
-            selectedDate = today.toISOString().split('T')[0];
+            const todayStr = today.toISOString().split('T')[0];
+            document.getElementById('appointment_date').value = todayStr;
+            selectedDate = todayStr;
+            
+            // 默认选择今天的日期并显示时间段
+            selectDate(todayStr);
             
             // 移动端优化
             if (/Mobi|Android|iPhone|iPad|iPod/i.test(navigator.userAgent)) {

packages.php

@@ -1,13 +1,6 @@
 <?php
-session_start();
 require_once 'db_connect.php';
 
-// 检查是否已登录
-if (!isset($_SESSION['admin_logged_in']) || $_SESSION['admin_logged_in'] !== true) {
-    header('Location: index.php');
-    exit();
-}
-
 $message = '';
 
 // 处理套餐操作