It unfortunately doesn't seem possible, even with a custom ruleguard rule, to mark a function as requiring it's return value be used, it looks like you have to go all in on a linter that rejects *any* unused return values.
This change adds a new `ReportConnection` endpoint to the `agentapi`.
The protocol version was bumped previously, so it has been omitted here.
This allows the agent to report connection events, for example when the
user connects to the workspace via SSH or VS Code.
Updates #15139
