Allow zk_inception ecosystem init not init the chain by default

[fyInALT]

🌟 Feature Request

📝 Description

Add a arg to zk_inception ecosystem init, make zk_inception not init the default chain.

🤔 Rationale

When use zk_inception ecosystem init, it will init the chain by default, it works well to run a devnet, but in some case, we need make some changes to chain config, so it better to add a arg to make tool not init the chain.

[EmilLuta]

cc: @Deniallugo, @zk-Lumi

[sanekmelnikov]

Added in #2946
zk_inception ecosystem init --ecosystem-only