Emit "message" event for IBC relayer

[yito88]

Bug Summary

Each handler should emit also "message" event for IBC relayer according to https://github.com/cosmos/ibc-go/blob/main/docs/ibc/events.md

Details

In Namada testing, after executing sending a token, Hermes wasn't notified because the message event wasn't emitted.

ibc-rs/crates/ibc/src/core/ics04_channel/handler/send_packet.rs

Line 124 in 2d64819

ctx_a.emit_ibc_event(IbcEvent::SendPacket(SendPacket::new(

Hermes' monitor subscribes to the IBC-specific events with message.module.
https://github.com/informalsystems/hermes/blob/a285c015c604819b213c1582d901e5ef140d3f47/crates/relayer/src/event/monitor.rs#L147-L165

Version

0.32.0

[plafer]

Interesting, when implementing #137, I had initially added this event, but then removed in after I realized that it was an "internal event" for SDK chains (used internally to route the event or something). I'm surprised that hermes needs it; let me look into that.

[plafer]

Agreed, let's emit these events too, as hermes does indeed rely on them for relaying.

Opened informalsystems/hermes#3190 so that hopefully we can remove them at some point is the future.