Issue description

tmux is wonderful, but I miss recenter-top-bottom (usually bound to C-l) from emacs quite a bit when I'm in copy mode.

If it's reasonable to provide pointers on how that might be implemented, I'd be interesting in giving it a shot.

Required information

Please provide the following information. These are required. Note that bug reports without logs may be ignored or closed without comment.

• tmux version (tmux 3.5a).
• Platform (Darwin arm).
• Terminal in use (iterm2).
• $TERM inside tmux (xterm-256color).
• $TERM outside tmux (xterm-256color).