message: Log warnings when observer called unexpected events.
diff: @@ -5,6 +5,8 @@ use super::{
  validators::Validators,
  vertex::{Dependency, Vertex, WireVote},
  };
  +use tracing::warn;
  +
  use crate::components::consensus::highway_core::vertex::SignedWireVote;
  use crate::components::consensus::traits::Context;
  @@ -78,7 +80,7 @@ impl<C: Context> Highway<C> {
  match self.active_validator.as_ref() {
  None => {
  // TODO: Error?
  - // At least add logging about the event.
  + warn!(?vhash, %instant, "Observer node was called with `on_new_vote` event.");
  vec![]
  }
  Some(av) => av.on_new_vote(vhash, instant, &self.state),
  @@ -90,6 +92,7 @@ impl<C: Context> Highway<C> {
  None => {
  // TODO: Error?
  // At least add logging about the event.
  + warn!(%instant, "Observer node was called with `handle_timer` event.");
  vec![]
  }
  Some(av) => av.handle_timer(instant, &self.state),
  @@ -104,7 +107,7 @@ impl<C: Context> Highway<C> {
  match self.active_validator.as_ref() {
  None => {
  // TODO: Error?
  - // At least add logging about the event.
  + warn!(?value, %block_context.instant, "Observer node was called with `propose` event.");
  vec![]
  }
  Some(av) => av.propose(value, block_context, &self.state),
  