Bundled engine tools refreshed for Unity, Godot and Unreal

The engine command-line tools shipped with the app are updated to Unity MCP 0.93.4, Godot MCP 0.26.1 and Unreal MCP 0.20.2, all built against the shared MCP server 9.2.11 and MCP-Plugin 8.7.1. The shared server now tells a cancelled request apart from a real timeout, so connection problems are easier to read when something goes wrong.