Added getAttrs functions to parseHTML in tiptap-button-extension.ts.
Now properly extracts text/href/style from DOM elements:
- data-button: extracts from data-text, data-href, data-style
- a.button: extracts text/href, defaults to solid style
- a.button-outline: extracts text/href, defaults to outline style
This fixes the issue where buttons appeared unstyled (outline
instead of solid) when editing a card that contained buttons.