Tezlink/Tezt Cloud: TzKT processes colors

Contributes to L2-268.
Rebases on !18896 (merged).

What

Use the same colors as those of the EVM node.

Why

Preserve color consistency in case of a change, which eases reading the matrix for those who can and do.

How

Expose. Use.

Manually testing the MR

Run dune exec tezt/tests/cloud/main.exe -- TEZLINK --tezt-cloud tezlink --localhost -v --color before and after, and see how nothing has changed about the colors of messages in your terminal.