zsh: save history in cache directory

bootstrap

@@ -30,6 +30,7 @@ ${HOME}/.local/etc/git
 ${HOME}/.jupyter/custom
 ${HOME}/.jupyter/nbconfig
 ${HOME}/.ssh
+${XDG_CACHE_HOME}/zsh
 ${XDG_CONFIG_HOME}/alacritty
 ${XDG_CONFIG_HOME}/git
 ${XDG_CONFIG_HOME}/mintty

files/zshrc

@@ -9,3 +9,8 @@ unset f
 
 stty stop undef # Prevent ctrl-s from freezing the terminal.
 
+# Save a lot of history in the cache directory.
+HISTFILE="${XDG_CACHE_HOME:-$HOME/.cache}/zsh/history"
+HISTSIZE=1000000
+SAVEHIST=1000000
+