Signal has a fork of curve25519-dalek to add some features that are used by zkgroup. However, libsignal-protocol and poksho don't use those features directly, and thus they don't depend on our fork specifically. Anyone outside of Signal using libsignal-protocol can thus use the standard curve25519-dalek and avoid building it twice. Signal will continue using our fork thanks to the workspace patch in the root Cargo.toml.
Additionally, remove all the passthrough features for customizing curve25519-dalek; we don't use any of them, and clients can always specify them directly.
Signal has a fork of curve25519-dalek to add some features that are used by zkgroup. However, libsignal-protocol and poksho don't use those features directly, and thus they don't depend on our fork specifically. Anyone outside of Signal using libsignal-protocol can thus use the standard curve25519-dalek and avoid building it twice. Signal will continue using our fork thanks to the workspace patch in the root Cargo.toml.
Additionally, remove all the passthrough features for customizing curve25519-dalek; we don't use any of them, and clients can always specify them directly.