Sdl backend (#670)

* [audio] added sdl audio backend and in-tree atrac9 decoder

* [input] replaced per-platform pad readers with sdl gamepad input

* [video] added sdl window and host display plumbing

* [gui] added host display options and per-game render settings

* [bink] synced host movie playback to the guest audio clock

* [cpu] hooked windows write faults into guest image tracking

* [perf] added guest and render profiling, reserved host cpu lanes

* [kernel] fixed stale pthread mutex handle alias

* [host] wired the sdl session, save-data paths and project references

* [audio] hoisted ajm trace stackalloc out of its loop

* [video] Add guest image sync setting

* [build] Strip native symbols

* reuse

src/SharpEmu.HLE/Host/WindowHostInput.cs

@@ -0,0 +1,43 @@
+// Copyright (C) 2026 SharpEmu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+namespace SharpEmu.HLE.Host;
+
+/// <summary>
+/// Routes emulated input through the active cross-platform host window.
+/// </summary>
+internal sealed class WindowHostInput : IHostInput
+{
+    public void EnsureStarted()
+    {
+        // SDL owns device discovery and pumps it on the window thread.
+    }
+
+    public int GetGamepadStates(Span<HostGamepadState> destination) =>
+        HostWindowInputSource.Current?.GetGamepadStates(destination) ?? 0;
+
+    public string? DescribeConnectedGamepad() =>
+        HostWindowInputSource.Current?.DescribeConnectedGamepad();
+
+    public void SetRumble(byte largeMotor, byte smallMotor) =>
+        HostWindowInputSource.Current?.SetRumble(largeMotor, smallMotor);
+
+    public void SetTriggerRumble(byte? leftTrigger, byte? rightTrigger) =>
+        HostWindowInputSource.Current?.SetTriggerRumble(leftTrigger, rightTrigger);
+
+    public void SetAdaptiveTriggerEffect(
+        HostAdaptiveTriggerEffect? leftTrigger,
+        HostAdaptiveTriggerEffect? rightTrigger) =>
+        HostWindowInputSource.Current?.SetAdaptiveTriggerEffect(leftTrigger, rightTrigger);
+
+    public void SetLightbar(byte red, byte green, byte blue) =>
+        HostWindowInputSource.Current?.SetLightbar(red, green, blue);
+
+    public void ResetLightbar() => HostWindowInputSource.Current?.ResetLightbar();
+
+    public bool IsHostWindowFocused() =>
+        HostWindowInputSource.Current?.HasKeyboardFocus ?? false;
+
+    public bool IsKeyDown(int virtualKey) =>
+        HostWindowInputSource.Current?.IsKeyDown(virtualKey) ?? false;
+}