Import Oxide engine (Stages 0–10) under MIT license

Full project snapshot migrated to new Gitea remote without history:
engine, editor, physics, script, examples, tests, docs, and assets.
Relicensed from GPLv3 to MIT and updated repo URLs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

engine/src/window/mod.rs

@@ -0,0 +1,63 @@
+//! Windowing and the application event loop.
+//!
+//! Stage 2 scope: open a window via `winit`, hand its surface to the
+//! [`render`](crate::render) module, and run a clear-color render loop.
+//! Applications implement [`WindowApp`] and are driven by [`run`]; raw window
+//! events (keyboard, mouse, resize, …) are forwarded to
+//! [`WindowApp::event`] untranslated — input abstraction arrives in Stage 5.
+//!
+//! Stage 6 renamed this trait from `App` to `WindowApp` so the engine's core
+//! [`App`](crate::app::App) container — the owner of scene, assets, and
+//! scheduled systems — can live in the prelude unambiguously. The two are
+//! distinct roles: this trait is the **window-event handler** the editor and
+//! examples implement; the core `App` is the engine state they typically wrap
+//! around.
+
+mod app;
+mod runner;
+
+pub use app::{AppCtx, RenderCtx, WindowApp};
+pub use runner::run;
+
+pub mod event {
+    //! Raw window/input event types, re-exported from `winit`.
+    //!
+    //! Stage 2 deliberately exposes events untranslated; the Stage 5 input
+    //! system will layer action mapping on top of these.
+    pub use winit::dpi::{PhysicalPosition, PhysicalSize};
+    pub use winit::event::{
+        DeviceEvent, DeviceId, ElementState, KeyEvent, Modifiers, MouseButton, MouseScrollDelta,
+        WindowEvent,
+    };
+    pub use winit::keyboard::{Key, KeyCode, ModifiersState, NamedKey, PhysicalKey};
+}
+
+use crate::math::Color;
+
+/// Initial window settings, consumed by [`run`].
+#[derive(Debug, Clone)]
+pub struct WindowConfig {
+    /// Window title.
+    pub title: String,
+    /// Initial inner width in logical pixels.
+    pub width: u32,
+    /// Initial inner height in logical pixels.
+    pub height: u32,
+    /// Whether the user can resize the window.
+    pub resizable: bool,
+    /// Color the surface is cleared to each frame (changeable at runtime via
+    /// [`AppCtx::set_clear_color`]).
+    pub clear_color: Color,
+}
+
+impl Default for WindowConfig {
+    fn default() -> Self {
+        Self {
+            title: "Oxide".to_string(),
+            width: 1280,
+            height: 720,
+            resizable: true,
+            clear_color: Color::BLACK,
+        }
+    }
+}