fix: zkstack readme update broken links and wording

[zk-Lumi]

What ❔

Hi @Deniallugo @popzxc 👋

Was playing with zkstack cli today.

This PR is just fixing a couple of broken links and updating a bit of wording in zkstack_cli/README.md.

PS: sidenote, "EVM emulator" is not explained in this readme, and "Enable EVM emulator?" in interactive mode will be confusing to people (they likely wont realize that it is emulating EVM equivalence but not required for most chains + will be more expensive)

Why ❔

Possibly a bit OCD, ie "Zk" being wrongly cased in one instance stayed in my mind and bothered me hahahah 😉

Checklist

• PR title corresponds to the body of PR (we generate changelog entries from PRs).
• Tests for the changes have been added / updated.
• Documentation comments have been added / updated.
• Code has been formatted via zkstack dev fmt and zkstack dev lint.

[popzxc]

PS: sidenote, "EVM emulator" is not explained in this readme, and "Enable EVM emulator?" in interactive mode will be confusing to people (they likely wont realize that it is emulating EVM equivalence but not required for most chains + will be more expensive)

cc @sanekmelnikov