v0.9.0: sheets with names and webp

• added option to get sheets using their name (string)
• added webp as an option to image formats

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verified schema: exdschema@9942dd96c70dfbba55bbc4280da144e5cb410737-2024.11.06.0000.0000
verified version: 7.15

Full Changelog: v0.8.0...v0.9.0