feat: 添加开发者社交链接功能和管理员系统信息页面

- 在developers表中添加social_links字段用于存储开发者社交链接
- 新增开发者个人资料编辑页面(profile.php)
- 在开发者应用页面展示社交链接
- 新增管理员系统信息页面(system_info.php)用于管理上传文件
- 更新导航菜单添加相关功能入口
- 修复平台图标显示问题并优化Font Awesome引用方式

app_store.sql

@@ -198,6 +198,10 @@ EXECUTE stmt;
 DEALLOCATE PREPARE stmt;
 
 SET @exist_fk = (SELECT COUNT(*) FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'apps' AND COLUMN_NAME = 'developer_id' AND CONSTRAINT_NAME = 'fk_apps_developers');
+
+-- 添加 social_links 字段到 developers 表
+ALTER TABLE developers
+ADD COLUMN social_links VARCHAR(255) DEFAULT '' AFTER password;
 SET @sql = IF(@exist_fk = 0, 'ALTER TABLE apps ADD CONSTRAINT fk_apps_developers FOREIGN KEY (developer_id) REFERENCES developers(id) ON DELETE SET NULL', 'SELECT 1');
 PREPARE stmt FROM @sql;
 EXECUTE stmt;