GH-76829
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Validate extension JSON: Error: Field 'classes/RichTextLabel/methods/add_image/arguments': size changed value in new API, from 6 to 11.
Validate extension JSON: Error: Field 'classes/RichTextLabel/methods/add_image/arguments': size changed value in new API, from 10 to 11.
Validate extension JSON: Error: Field 'classes/RichTextLabel/methods/push_table/arguments': size changed value in new API, from 3 to 4.
Validate extension JSON: Error: Field 'classes/TreeItem/methods/add_button/arguments': size changed value in new API, from 5 to 6.

Added optional arguments. Compatibility methods registered.
