`filter-branch` / rebase imminent in the coming weeks

Same as https://github.com/tmux-python/tmuxp/issues/732, I want to cut down bloat in the repositories.

I will run the same cleanup on tmuxp I do on libtmux, but will also try to curate some screenshots/animated gifs and optimize them well

Potentially i will move binary images to gh-pages or a branch. Not sure.

This is one time thing. Also I think we're too small for git-lfs to make sense but I will investigate the tradeoffs of that.

If we used git-lfs and it didn't break stuff downstream, I'd be much more willing to commit screenshots / graphics and styling.

On word on docs

1. Further I am concerned that us moving documentation to a different project, e.g. from sphinx to docusaurus, is going to bloat the repo size further. I am still investigating solutions with that.

2. I am going to investigate porting our docs so they have versioning back to past releases. The problem is if we go with docusaurus, I am concerned on us having a perfect alignment of page links

No files, tests, or entry points are named. Start by reviewing the linked tmuxp issue and the repository-cleanup plans in this issue, then decide whether history cleanup, image relocation, Git LFS, or documentation versioning is in scope. Done should include an agreed approach that reduces repository bloat without breaking downstream use or documentation links.