feat: use docker by default for gnark

[ctian1]

• plonk feature is now native-gnark in sdk and prover. In gnark-ffi the plonk feature is now native
• recursion/gnark-cli crate calls native gnark functions as a simple cli
• When not using native-gnark, Docker is used instead of panicking
• Build gnark docker image in CI
• Separate docker test in CI because main tests in docker dont work well concurrently

CLI code adopted from #866

[mattstam]

here