Implement ISelectionProvider and ISelectionItemProvider

[chiaramooney]

Description

Type of Change

• New feature (non-breaking change which adds functionality)

Why

Accessibility on the new architecture should reach parity with Paper.

Resolves https://github.com/microsoft/react-native-windows/issues/13064 Resolves https://github.com/microsoft/react-native-windows/issues/13060 Resolves https://github.com/microsoft/react-native-windows/issues/13056 Resolves https://github.com/microsoft/react-native-windows/issues/13052 Resolves https://github.com/microsoft/react-native-windows/issues/13048 Resolves https://github.com/microsoft/react-native-windows/issues/13044 Resolves https://github.com/microsoft/react-native-windows/issues/13040 Resolves https://github.com/microsoft/react-native-windows/issues/13036 Resolves https://github.com/microsoft/react-native-windows/issues/13032 Resolves https://github.com/microsoft/react-native-windows/issues/12047 https://github.com/microsoft/react-native-windows/issues/13327 https://github.com/microsoft/react-native-windows/issues/13316

Resolves https://github.com/microsoft/react-native-windows/issues/13354 Resolves https://github.com/microsoft/react-native-windows/issues/13353

What

• Adds support for ISelectionProvider interface
• Adds support for ISelectionItemProvider interface
• Adds support for accessibilityState:selected
• Adjusts AccessibilityState native type on Windows to be std::optional instead of bool
• Adjusts AccessibilityState native type on Windows to include multiselectable and required fields of type std::optional
• Adds multiselectable and required fields to AccessibilityState type in JS with type boolean | undefined
• Adds support for aria-multiselectable and aria-required.
• Adds support for the following accessibilityActions: addToSelection, removeFromSelection, select
• Fixes crash in AccessibilityInsights.

Testing

Locally tested for:

• ISelectionItemProvider: AddToSelection, RemoveFrommSelection, Select, get_IsSelected, get_SelectionContainer
• ISelectionProvider:  GetSelection, get_CanSelectMultiple, get_IsSelectionRequired
• Parent as selection container, Non-parent ancestor as selection container
• Adding/Removing SelectionItem from the Visual Tree
• Adding/Removing SelectionContainer from Visual Tree
• Calling addToSelection, removeFromSelection, and select accessibilityActions
• Adjusting values of accessibilityState multiselectable and required
• Child views that aren't selectable items
• Selection of multiple items

Changelog

Should this change be included in the release notes: Yes