Add MRC-17: PropAMM Router Interface

[haythemsellami]

New MRC, draft.

This MRC defines a standard routing interface for propAMMs.

Forum post: https://forum.monad.xyz/t/mrc-17-propamm-routing-interface/

[ShadowOfTime1]

I build against this exact pattern (the moss Kuru adapter quotes by eth_call-ing the swap path), so two things from running it on mainnet:

1. The spec gives a venue no way to say "I can't fill right now" as distinct from "the quote failed." Every failure of getAmountOut is a revert, so a router cannot tell a paused or empty venue from a broken quote or an out-of-gas frame. That matters for any router that compares venues exhaustively. On mainnet, one Kuru MON/USDC market reverted every quote with MarketStateError() for two weeks, and a strict comparison refused the whole pair even though three other markets filled. Could the MRC standardize the signal? For example, a venue that cannot fill MUST return amountOut = 0 rather than revert, or a standard PropAMMUnavailable() error, so that a revert unambiguously means failure.

2. Quote expiry isn't exposed. Execution is guaranteed "before its expiry", but the expiry only lives inside opaque swapData, so a router can't tell when to requote. Would an explicit validUntil return, or a standard error for stale swapData, fit here?

[QEDK]

Some thoughts.

[QEDK]

LGTM.