Announcing Support for Form-Associated Custom Elements in Stencil v4.5.0

As of version 4.5.0, Stencil now supports form-associated custom elements, allowing developers to build custom elements that integrate seamlessly with form elements using built-in browser functionalities like validation and accessibility. This feature utilizes the ElementInternals interface, enabling web component developers to create custom elements that interact richly with forms, similar to native HTML inputs. Stencil introduces a new option, `formAssociated`, for the `@Component` decorator, and a new `@AttachInternals` decorator, allowing components to access ElementInternals. An example implementation of a custom text input demonstrates how form-associated custom elements can automatically connect with surrounding forms, using methods such as `setFormValue` to assign values to form elements. This advancement opens up a range of possibilities for Stencil components in form interactions, enhancing their capabilities in form management and data handling.