refactor: split Passage enter/exit from Orders

[anna-carroll]

current PR TODO

• fix however this probably breaks CI (e.g. 2 contracts now instead of 1)

[anna-carroll]

i do think this is conceptually cleaner.

• Passage — enter/exit — manages mint/burn Ether and tokens

  • custodies TVL of the rollup on host chain.
    • only withdrawalAdmin multisig can take funds out on the host.
  • holds ERC20 mint/burn permissions on rollup.
    • accessible via transact flow via hostPassage address.
  • Node must watch this contract to mint/burn native Ether.
  • (soon) Node must watch this contract for transact flow.

• Market — swap/fill/sweep — manages intent-based Orders

  • doesn’t custody any funds or permissions.
  • Node must watch this contract to check for intent fulfillment.

[prestwich]

directionally I approve. seems there are some TODOs

[anna-carroll]

note: ERC20 enters/exits are not specced yet, so i'm removing those functions from this PR for now: 9c6438a

if we decide not to implement them, it would make more sense to remove the token field from the Enter event (as it would always be address(0) - native ether).

let's decide on ERC20 plan then ossify that event interface.

[prestwich]

i would delete the exit code, as we haven't specified this behavior, and we don't know if the code is appropriate for it