Enatega Customer Application: Also remove the heading Default category from restaurant details card

Describe the bug
Remove the heading Default category from restaurant details card showing up on discovery screen. In case If there is no food category selected show blank on the restaurant card.

To Reproduce
Steps to reproduce the behavior:

Go to 'Enatega Customer Application'.
Now see on Discovery page , the restaurant cards right below the restaurant name there is the heading Default Food Category when no food category is selected by the user.
Expected behavior
If a food category is selected for a restaurant, it should display the selected category on the restaurant card.
If no food category is selected, the category heading should be blank or not shown at all (depending on design guidelines).

Screenshots

Screen_Recording_20250127_155156.mp4
Smartphone (please complete the following information):

Device: [e.g. Infinix Hot 50]
OS: [e.g.Android]
Browser [e.g. Application]
Version [e.g. Latest]

从 Enatega Customer Application 的发现界面开始，找到餐厅名称下方显示的餐厅卡片。复现未选择任何食物类别的情况，然后检查卡片如何渲染类别标题。当已选择的类别仍然显示，并且不存在任何类别时 Default Food Category 标题不显示或为空时，即表示完成。

由索引模型根据 Issue 内容生成。