[core, hle, video_core, memory] Improve multi-process, display layers, dynamic shader cache and rework overlay (#4238)

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

- Dynamic shader cache reloading capability for qlaunch
- Multi-process improvements (thanks to @frank1734), instead of just using the main application we now respect caller process (also did it for HID devices while I was at it)
- Layer stack masks & shared buffer screenshot for video core, added different masks (screenshot, recording, etc.) this was discovered as an issue due to how in qlaunch the transition was not right between applications. May not be perfect but also fixes screenshots while using qlaunch
- Reworked overlay display management (input and visibility) - instead of random numbers as I've previously did, I decided to add an AppletZIndex enum for better readability. Also split capability of input by touch and gamepad.
- etc.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4238
Reviewed-by: Samuel <lizzie@eden-emu.dev>
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

src/hid_core/resources/six_axis/seven_six_axis.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
@@ -6,6 +9,7 @@
 #include "core/core.h"
 #include "core/core_timing.h"
 #include "core/frontend/emu_window.h"
+#include "core/hle/kernel/k_process.h"
 #include "core/memory.h"
 #include "hid_core/frontend/emulated_console.h"
 #include "hid_core/frontend/emulated_devices.h"
@@ -24,7 +28,7 @@ void SevenSixAxis::OnInit() {}
 void SevenSixAxis::OnRelease() {}
 
 void SevenSixAxis::OnUpdate(const Core::Timing::CoreTiming& core_timing) {
-    if (!IsControllerActivated() || transfer_memory == 0) {
+    if (!IsControllerActivated() || transfer_memory == 0 || transfer_memory_owner == nullptr) {
         seven_sixaxis_lifo.buffer_count = 0;
         seven_sixaxis_lifo.buffer_tail = 0;
         return;
@@ -51,12 +55,13 @@ void SevenSixAxis::OnUpdate(const Core::Timing::CoreTiming& core_timing) {
     };
 
     seven_sixaxis_lifo.WriteNextEntry(next_seven_sixaxis_state);
-    system.ApplicationMemory().WriteBlock(transfer_memory, &seven_sixaxis_lifo,
-                                          sizeof(seven_sixaxis_lifo));
+    transfer_memory_owner->GetMemory().WriteBlock(transfer_memory, &seven_sixaxis_lifo,
+                                                  sizeof(seven_sixaxis_lifo));
 }
 
-void SevenSixAxis::SetTransferMemoryAddress(Common::ProcessAddress t_mem) {
+void SevenSixAxis::SetTransferMemoryAddress(Common::ProcessAddress t_mem, Kernel::KProcess* owner) {
     transfer_memory = t_mem;
+    transfer_memory_owner = owner;
 }
 
 void SevenSixAxis::ResetTimestamp() {

src/hid_core/resources/six_axis/seven_six_axis.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
@@ -9,6 +12,10 @@
 #include "hid_core/resources/controller_base.h"
 #include "hid_core/resources/ring_lifo.h"
 
+namespace Kernel {
+class KProcess;
+}
+
 namespace Core {
 class System;
 } // namespace Core
@@ -33,7 +40,7 @@ public:
     void OnUpdate(const Core::Timing::CoreTiming& core_timing) override;
 
     // Called on InitializeSevenSixAxisSensor
-    void SetTransferMemoryAddress(Common::ProcessAddress t_mem);
+    void SetTransferMemoryAddress(Common::ProcessAddress t_mem, Kernel::KProcess* owner);
 
     // Called on ResetSevenSixAxisSensorTimestamp
     void ResetTimestamp();
@@ -58,6 +65,7 @@ private:
 
     SevenSixAxisState next_seven_sixaxis_state{};
     Common::ProcessAddress transfer_memory{};
+    Kernel::KProcess* transfer_memory_owner{};
     Core::HID::EmulatedConsole* console = nullptr;
 
     Core::System& system;

src/hid_core/resources/touch_screen/touch_screen_resource.cpp

@@ -548,8 +548,18 @@ void TouchResource::OnTouchUpdate(s64 timestamp) {
             }
 
             auto& touch_shared = applet_data->shared_memory_format->touch_screen;
-            StorePreviousTouchState(previous_touch_state, data.finger_map, current_touch_state, bool(applet_data->flag.enable_touchscreen));
-            touch_shared.touch_screen_lifo.WriteNextEntry(current_touch_state);
+
+            if (applet_data->flag.enable_touchscreen) {
+                StorePreviousTouchState(previous_touch_state, data.finger_map, current_touch_state, true);
+                touch_shared.touch_screen_lifo.WriteNextEntry(current_touch_state);
+            } else {
+                TouchScreenState denied{};
+                denied.sampling_number = current_touch_state.sampling_number;
+                denied.entry_count = 0;
+                data.finger_map.finger_count = 0;
+                data.finger_map.finger_ids = {};
+                touch_shared.touch_screen_lifo.WriteNextEntry(denied);
+            }
         }
     }
 }