Since [1], a fix was introduced to display the actual value of a relational field instead of its ID. However, another issue occurs when a form is inside a tab (Tabs snippet) and a new tab is added. During this process, the currently active tab is cloned, including its field IDs. Although a method exists to update the IDs after cloning, the form rendering is triggered beforehand.

This causes the labels property of input elements—which is expected to return a NodeList of associated <label> elements—to fail because the cloned input IDs are not unique.

This commit resolves the issue by using querySelector to target the associated label elements directly.

Steps to reproduce:

- Open the Website editor.
- Drag & Drop a Tabs snippet.
- In the first tab, drag & Drop a Form snippet.
- Set the first field as a radio buttons.
- Make the second field's visibility depend on the first field.
- Add a new tab by clicking the "+" icon in the right panel.
- Observe that a traceback occurs.

A second issue related to [1] has been resolved for cases where there is
only a single checkbox. In this scenario, the value displayed in the
visibility condition dropdown menu should be "Yes".

opw-4345340

[1]: https://github.com/odoo/odoo/commit/4b37f22cece5424d6992c6bafe619c9a457d184b

Forward-Port-Of: odoo/odoo#190460