feat(tmux): add prefix highlight plugin

tmux/.tmux.conf

@@ -203,7 +203,8 @@ set-option -g status-left "\
 
 set-option -g status-right "\
 #[fg=colour214, bg=colour237] \
-#[fg=colour223, bg=colour237] #(~/dotfiles/tmux/scripts/uptime.sh) \
+#[fg=colour223, bg=colour237]#{prefix_highlight} \
+#[fg=colour223, bg=colour237]  #(~/dotfiles/tmux/scripts/uptime.sh) \
 #[fg=colour246, bg=colour237]  %m/%d\
 #[fg=colour109]  %H:%M \
 #[fg=colour248, bg=colour239]"
@@ -244,6 +245,7 @@ set -g @plugin 'tmux-plugins/tmux-copycat'
 set -g @plugin 'christoomey/vim-tmux-navigator'
 set -g @plugin 'tmux-plugins/tmux-resurrect'
 set -g @plugin 'tmux-plugins/tmux-continuum'
+set -g @plugin 'tmux-plugins/tmux-prefix-highlight'
 
 # Other examples:
 # set -g @plugin 'github_username/plugin_name'