## Issue Addressed
NA
## Proposed Changes
Carries on from #4115, with the following modifications:
1. Self-hosted runners are only enabled if `github.repository == sigp/lighthouse`.
- This allows forks to still have Github-hosted CI.
- This gives us a method to switch back to Github-runners if we have extended downtime on self-hosted.
1. Does not remove any existing dependency builds for Github-hosted runners (e.g., installing the latest Rust).
1. Adds the `WATCH_HOST` environment variable which defines where we expect to find the postgres db in the `watch` tests. This should be set to `host.docker.internal` for the tests to pass on self-hosted runners.
## Additional Info
NA
Co-authored-by: antondlr <anton@delaruelle.net>
## Issue Addressed
Fixes occasional compilation errors with mev-rs (see #4456).
## Proposed Changes
- Update `mev-rs` to the latest version, which allows us to remove hacky `[patch]` sections
- Update the `axum` version used in `watch` so LH only uses a single version
> This is currently a WIP and all features are subject to alteration or removal at any time.
## Overview
The successor to #2873.
Contains the backbone of `beacon.watch` including syncing code, the initial API, and several core database tables.
See `watch/README.md` for more information, requirements and usage.
