Both the ImGui devtools ChatPanel and the upcoming retail chat window
now route through ChatCommandRouter.Submit so command handling lives in
one place. The ChatPanel inline block (TryHandleClientCommand / EqAny /
BuildHelpText) is deleted; ChatCommandRouter carries the same logic
verbatim. ChatPanel.Render becomes a 2-line delegate.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>