NOTE
Netty Pipeline: Inbound Events
Propagation of channel lifecycle and read events through inbound handlers.
This is a historical learning note and may contain outdated or incomplete understanding.
Inbound events represent data/lifecycle signals flowing from transport toward application handlers—for example registered/active/read/read-complete/user events.
An inbound handler processes an event and normally calls the corresponding ctx.fire... method to pass it to the next eligible inbound context. Consuming an event without forwarding is intentional only when that handler owns the event/data.
For reference-counted messages, ownership/release must remain correct when an event is consumed or transformed.