Agglayer: restructure `asm` directory

[partylikeits1983]

The file layout of the crates/miden-agglayer/asm directory should be updated to follow this layout:

asm
├── agglayer
│   ├── bridge
│   │   ├── asset_conversion.masm
│   │   ├── bridge_in.masm
│   │   ├── bridge_out.masm
│   │   ├── crypto_utils.masm
│   │   ├── eth_address.masm
│   │   └── local_exit_tree.masm
│   ├── faucet
│   │   └── mod.masm
│   └── notes
│       ├── b2agg.masm
│       └── claim.masm
├── components
│   ├── bridge.masm
│   └── faucet.masm
└── notes
    ├── b2agg.masm
    └── claim.masm

Source: #2107 (review)

[mmagician]

The proposed structure looks good, but let's make sure we focus on non-feature changes for Agglayer only once bridging in & out flows are both complete.

[mmagician]

We should also look into a better responsibility split across the individual files:

• bridge_in.masm and crypto_utils.masm distinction is not super clear
• similarly for bridge_out.masm and local_exit_tree.masm

[mmagician]

The current setup actually leads to an incorrect setup, since we end up with a single library which all the components use.

pub fn agglayer_library() -> Library {
    AGGLAYER_LIBRARY.clone()
}

pub fn bridge_out_library() -> Library {
    agglayer_library()
}

pub fn agglayer_faucet_library() -> Library {
    agglayer_library()
}

So if I'm not mistaken, both the bridge and the faucet will contain all the components (bridge + faucet + any other pub procedures), which can lead to vulnerabilities (e.g. the bridge account exposing claim)

So this should be re-structured sooner rather than later, so that each component has its own library.

[bobbinth]

Yes, each component should have it's own library, but I think we should follow the same structure as we do in miden-standards:

• The actual functionality is defined in the AggLayer library.
• Component libraries are largely just think wrappers that re-export relevant functionality from the AggLayer library.