This looks like a really useful plugin, thanks for your efforts. I use a variety of PDF highlight extractors already, and it would be great to have this integrated into Obsidian.
Suggestion: Add the option of including the page header as well as the page # in the extracted highlight. This would mean e.g. that the chapter title or document heading of part of the PDF would be associated with the highlight, and would give it context. Personally I need this as I review large medical files with reports from various people, and this would help me associate the highlight with the relevant section.