feat(cli)!: add omz reload command and deprecate zsh_reload plugin (#9078)

BREAKING CHANGE: the `zsh_reload` plugin is deprecated. Instead of using its `src`
function, use `omz reload` or `exec zsh` to reload zsh after making changes to
your `.zshrc` file.

Closes #9078

plugins/zsh_reload/zsh_reload.plugin.zsh

@@ -1,22 +1,7 @@
+print ${(%):-"%F{yellow}The \`zsh_reload\` plugin is deprecated and will be removed."}
+print ${(%):-"Use \`%Bomz reload%b\` or \`%Bexec zsh%b\` instead.%f"}
+
 src() {
-	local cache="$ZSH_CACHE_DIR"
-	autoload -U compinit zrecompile
-	compinit -i -d "$cache/zcomp-$HOST"
-
-	for f in ${ZDOTDIR:-~}/.zshrc "$cache/zcomp-$HOST"; do
-		zrecompile -p $f && command rm -f $f.zwc.old
-	done
-
-	# Use $SHELL if it's available and a zsh shell
-	local shell="$ZSH_ARGZERO"
-	if [[ "${${SHELL:t}#-}" = zsh ]]; then
-		shell="$SHELL"
-	fi
-
-	# Remove leading dash if login shell and run accordingly
-	if [[ "${shell:0:1}" = "-" ]]; then
-		exec -l "${shell#-}"
-	else
-		exec "$shell"
-	fi
+  print ${(%):-"%F{yellow}$0 is deprecated. Use \`%Bomz reload%b\` or \`%Bexec zsh%b\` instead.%f\n"}
+  omz reload
 }