- adds HandleChannelConnection (server-side conn-to-channel upgrade) and the
client-side NewChannel/ConnToChannel/MakeChannelRequest helpers to common/agent;
these import channel/v4 + identity, which are already root-module deps, so there
is no go.mod or Go-version change
- replaces the duplicated agent channel-upgrade handlers in controller, router,
tunnel, and demo with one-line delegations to common/agent.HandleChannelConnection
- moves the CLI-side channel dialer (was NewAgentChannel/connToChannelMapper/
MakeAgentChannelRequest in agentcli) into common/agent and repoints the agentcli
and demo callers
- normalizes the demo echo-server to accept the AppIdAny wildcard, matching the
other agent servers; previously it rejected it
- preserves the wire protocol (leading app-id byte, "agent" channel, 1s connect
timeout), so existing channel-based agent commands are unchanged
Paul Lorenz
9483c39bbd