/claim #35898Resolves#35898
### Summary of key changes:
1. Add file name search/Go to file functionality to repo button row.
2. Add backend functionality to delete directory
3. Add context menu for directories with functionality to copy path & delete a directory
4. Move Add/Upload file dropdown to right for parity with Github UI
5. Add tree view to the edit/upload UI
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
1. Add some "render-content" classes to "markup" elements when the
content is rendered
2. Use correct "markup" wrapper for "preview" (but not set that class on
the tab)
3. Remove incorrect "markup" class from LFS file view, because there is
no markup content
* "edit-diff" is also removed because it does nothing
5. Use "initPdfViewer" for PDF viewer
6. Remove incorrect "content" class from milestone markup
7. Init all ".markup" elements by new init framework
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Reorganize various CSS files for clarity, group together by subdirectory
in `index.css`. This reorders some of the rules, but I don't think it
should introduce any issues because of that.
