Feature: Widget templates in companion app

[nickeidler]

Background

I have a use case where I show the same set of widgets (i.e. inside temperature, outside temperature) on multiple different lock screens. In the current widget implementation I need to copy paste all of the label template fields whenever I create a new lock screen or add the widget to a new page.

Motivation

Reduce effort to create multiple versions of the same widget.

Proposed implementation

The below implementation is inspired by the Apple Watch complication setup flow.

1. Add a "Widget Template" or "Widget Blueprint" section to the existing "Widget" screen in the Companion App UI that allows the user to create and edit widget templates.
2. When adding widgets, allow for the user to reference an existing "Blueprint" defined above instead of entering the form fields during widget creation.

This will make it a lot easier to "duplicate" widgets across lock screens / pages. Also, when the "blueprint" is edited from the companion app, update the widgets accordingly. That way the user won't need to manually edit each widget every time something changes (i.e. swapping out temperature entities, adjusting template strings, etc).