refactor(input): own pointer and callback lifetime

Move camera pointer, framebuffer resize, and retained/devtools input edges behind focused reversible owners. Preserve input priority while making shutdown deactivate callbacks before live-session retirement and retry physical detach without stranding transport teardown.

src/AcDream.App/Rendering/FramebufferResizeController.cs

@@ -0,0 +1,118 @@
+using AcDream.App.Input;
+using Silk.NET.Maths;
+using Silk.NET.OpenGL;
+
+namespace AcDream.App.Rendering;
+
+internal interface IFramebufferViewportTarget
+{
+    void ResizeViewport(int width, int height);
+}
+
+internal sealed class SilkFramebufferViewportTarget(GL gl)
+    : IFramebufferViewportTarget
+{
+    private readonly GL _gl = gl ?? throw new ArgumentNullException(nameof(gl));
+
+    public void ResizeViewport(int width, int height) =>
+        _gl.Viewport(0, 0, (uint)width, (uint)height);
+}
+
+internal interface IFramebufferCameraTarget
+{
+    void SetAspect(float aspect);
+}
+
+internal sealed class CameraFramebufferTarget(CameraController camera)
+    : IFramebufferCameraTarget
+{
+    private readonly CameraController _camera = camera
+        ?? throw new ArgumentNullException(nameof(camera));
+
+    public void SetAspect(float aspect) => _camera.SetAspect(aspect);
+}
+
+internal interface IFramebufferDevToolsTarget
+{
+    void ResetLayout(int width, int height);
+}
+
+internal sealed class DevToolsFramebufferTarget(DevToolsFramePresenter presenter)
+    : IFramebufferDevToolsTarget
+{
+    private readonly DevToolsFramePresenter _presenter = presenter
+        ?? throw new ArgumentNullException(nameof(presenter));
+
+    public void ResetLayout(int width, int height) =>
+        _presenter.ResetLayout(
+            width,
+            height,
+            DevToolsPanelLayoutCondition.Always);
+}
+
+/// <summary>
+/// The one framebuffer-size target. Logical gameplay/UI dimensions continue
+/// to come from Window.Size; this owner only applies physical framebuffer
+/// viewport/aspect changes in the frozen acdream host order.
+/// </summary>
+internal sealed class FramebufferResizeController
+{
+    private readonly ViewportAspectState _viewportAspect;
+    private IFramebufferViewportTarget? _viewport;
+    private IFramebufferCameraTarget? _camera;
+    private IFramebufferDevToolsTarget? _devTools;
+
+    public FramebufferResizeController(ViewportAspectState viewportAspect) =>
+        _viewportAspect = viewportAspect
+            ?? throw new ArgumentNullException(nameof(viewportAspect));
+
+    public void BindViewport(IFramebufferViewportTarget viewport)
+    {
+        ArgumentNullException.ThrowIfNull(viewport);
+        BindOnce(ref _viewport, viewport, "viewport");
+    }
+
+    public void BindCamera(IFramebufferCameraTarget camera)
+    {
+        ArgumentNullException.ThrowIfNull(camera);
+        BindOnce(ref _camera, camera, "camera");
+    }
+
+    public void BindDevTools(IFramebufferDevToolsTarget devTools)
+    {
+        ArgumentNullException.ThrowIfNull(devTools);
+        BindOnce(ref _devTools, devTools, "developer tools");
+    }
+
+    public void UnbindDevTools(IFramebufferDevToolsTarget devTools)
+    {
+        ArgumentNullException.ThrowIfNull(devTools);
+        if (ReferenceEquals(_devTools, devTools))
+            _devTools = null;
+    }
+
+    public void Resize(Vector2D<int> newSize) => Resize(newSize.X, newSize.Y);
+
+    public void Resize(int width, int height)
+    {
+        if (width <= 0 || height <= 0)
+            return;
+
+        // Frozen order: GL viewport, shared aspect publication, camera, then
+        // optional ImGui layout reset. Late binding never replays an earlier
+        // resize transition.
+        _viewport?.ResizeViewport(width, height);
+        _viewportAspect.Update(width, height);
+        _camera?.SetAspect(width / (float)height);
+        _devTools?.ResetLayout(width, height);
+    }
+
+    private static void BindOnce<T>(ref T? slot, T value, string name)
+        where T : class
+    {
+        if (slot is not null && !ReferenceEquals(slot, value))
+            throw new InvalidOperationException(
+                $"The framebuffer {name} target is already bound.");
+        slot = value;
+    }
+}