めんどくさくなったので簡単に

/setblock ~ ~ ~ minecraft:standing_sign 0 replace {Text1:"{\"text\":\"右クリックしてください\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/setblock ~ ~ ~ minecraft:command_block 0 replace {TrackOutput:false,Command:\\\"/summon zombie ~ ~1 ~ {CustomName:\\\\\\\"\\u00a7f\\u00a7l\\u00a7nチョコレートゾンビ\\\\\\\",CustomNameVisible:1,ArmorItems:[{},{},{},{id:\\\\\\\"minecraft:stained_hardened_clay\\\\\\\",Damage:12,Count:1b}],ArmorDropChances:[0.085F,0.085F,0.085F,0.0F],Attributes:[{Name:generic.maxHealth,Base:10}],Health:10.0f}\\\"}\"}}",Text2:"{\"text\":\"\"}",Text3:"{\"text\":\"\"}",Text4:"{\"text\":\"\"}"}