feat: support adding TextNode elements (automatically sets text property by default)

[edusperoni]

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• Tests for the changes are included.

What is the current behavior?

TextNodes are ignored

What is the new behavior?

Any invisible node can be supported (through the invisible node meta property). By default, when a TextNode is added to a view, it sets the view.text property and listen to any changes on the TextNode and reapplies the text property.

This allows for the very neat:

<Label>This works! {{ someProperty | async }}</Label>