Remove certain dependencies from `eth2`, and feature-gate others which are only used by certain endpoints.
| Removed | Optional | Dev only |
| -------- | -------- | -------- |
| `either` `enr` `libp2p-identity` `multiaddr` | `protoarray` `eth2_keystore` `eip_3076` `zeroize` `reqwest-eventsource` `futures` `futures-util` | `rand` `test_random_derive` |
This is done by adding an `events` feature which enables the events endpoint and its associated dependencies.
The `lighthouse` feature also enables its associated dependencies making them optional.
The networking-adjacent dependencies were removed by just having certain fields use a `String` instead of an explicit network type. This means the user should handle conversion at the call site instead. This is a bit spicy, but I believe `PeerId`, `Enr` and `Multiaddr` are easily converted to and from `String`s so I think it's fine and reduces our dependency space by a lot. The alternative is to feature gate these types behind a `network` feature instead.
Co-Authored-By: Mac L <mjladson@pm.me>
Currently the `eth2` crate lib file is a large monolith of almost 3000 lines of code. As part of the bosun migration we are trying to increase code readability and modularity in the lighthouse crates initially, which then can be transferred to bosun
Co-Authored-By: hopinheimer <knmanas6@gmail.com>
Co-Authored-By: hopinheimer <48147533+hopinheimer@users.noreply.github.com>
