chore(ui5-toolbar-select): value and label added

[PetyaMarkovaBogdanova]

Fixes: 11706
This pull request introduces enhancements to the ToolbarSelect component, focusing on improved functionality for handling custom labels and values. Below is a summary of the most important changes:

Enhancements to ToolbarSelect Functionality:

• Support for Custom Labels:
  • Added a new label slot to allow custom HTML elements to be displayed as part of the component's input section. This enables dynamic customization of the label displayed alongside the select dropdown.
• Value Property Integration:
  • Added a new value property to correspond to the ui5-select 'value' prop. It is passed to the Select element in the wrapper component's template.

[dobrinyonkov]

Looking good, just a few stuff:

1) changing the selected option isn't updating the value property of the ui5-toolbar-select

• open ToolbarSelect.html
• change the selected option
• see the toolbarSelect.value property is returning old values

we may need to create a getter that returns the value property from the internal select
e.g

/**
 * Defines the value of the component:
 *
 * @public
 * @default ""
 * @since 2.13.0
 */
@property()
set value(newValue: string) {
	if (this.select) {
		this.select.value = newValue;
	}
}

get value() {
	return this.select ? this.select.value : "";
}

get select(): Select | null {
	return this.shadowRoot!.querySelector<Select>("[ui5-select]");
}

2) let's also create a new snippet in the ToolbarSelect.html

3) looks like we don't yet need individualSlots on the options slot 

[dobrinyonkov]

since 2.15.0