feat: disable plugin if fzf is not installed

zsh-fzf-history-search.zsh

@@ -1,4 +1,7 @@
-fzf_history_seach() {
+# do nothing if fzf is not installed
+(( ! $+commands[fzf] )) && return
+
+fzf_history_search() {
   setopt extendedglob
   candidates=(${(f)"$(fc -li -1 0 | fzf +s +m -x -e -q "$BUFFER")"})
   BUFFER="${candidates[@]/(#m)*/${${(As: :)MATCH}[4,-1]}}"
@@ -7,7 +10,7 @@ fzf_history_seach() {
   zle end-of-buffer-or-history
 }
 
-autoload fzf_history_seach
-zle -N fzf_history_seach
+autoload fzf_history_search
+zle -N fzf_history_search
 
-bindkey '^r' fzf_history_seach
+bindkey '^r' fzf_history_search