The `Engine.Install` entry point is the single cross-child wiring point: it loads `ClassicAssist.Shared.dll`, registers a `WPFDispatcher`/`WPFUIInvoker` on `SEngine`, installs `WPFMessageBoxProvider`, subscribes to `Options.LoadEvent`/`SaveEvent` to persist every `BaseViewModel` implementing `ISettingProvider`, then creates `MainWindow` on an STA thread. `WPFUIInvoker` exposes `IUIInvoker.Invoke`/`InvokeDialog` so the shared engine can open any `Window` subclass by name with optional DataContext — this is how hotkey commands in `Data/Hotkeys/Commands` (e.g. `ShowChatWindowCommand`, `ShowGIFCaptureWindow`) and other engine code trigger UI across the `main_ui`, `agents`, and `browser` view modules. All XAML resources are merged centrally via `Resources/ResourceDictionary.xaml` (dark theme, icons, colours), consumed uniformly by every child's Views. The project is split into presentation concerns (`Browser`, `UI/*`, `Agents`, `Main Window`) plus thin data helpers (`Data/Hotkeys`, `Data/Macros`, `Data/Skills`) that depend only on the shared engine abstractions rather than each other.