* refactor: basic split
* fix: renaming and usage test didn't work for the tests
* fix: tests
* refactor: restructuring
* refactor: further separation and lots of related changes
* refactor: remove last reference to a widget from controller
* refactor: address todo
* fix: failing tests and mypy compaint
* refactor: move control logic to controller
* refactor: more readable button style
* refactor: move existing code to view
* refactor: move existing code to controller
* fix: imports
* refactor: make methods private by default
* refactor: privatise fields
* refactor: reduce code duplication
* refactor: consolidate and sort display methods
* refactor: remove needless setting of delete action text
* refactor: extract control logic from _display_file
* refactor: use MediaType for __switch_preview
* fix: import in preview_panel_view.py
* refactor: remove unnecessary wrapper on view side
* refactor: move image data retrieval to control side
* refactor: move audio / video specific code to the respective method
* refactor: remove superfluos methods
* refactor: this and that
* refactor: use proper type instead of dict for file stats
* refactor: extract gif parsing to controller
* refactor: extract video size extraction to controller
* doc: add rule of thumb to Qt MVC Style Guide
* doc: change rule of thumb from note to tip
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Co-authored-by: Travis Abendshien <46939827+CyanVoxel@users.noreply.github.com>