Dear ImGui Implementation (#598)

* added imgui as dependency

* imgui renderer/basic input implementation

* imgui: add layers system

Add video info layer to show fps. Press F10 to toggle it.

* imgui: add custom imgui config

* imgui: gamepad capture, stopping propagation

* imgui: changed config & log file path to use portable dir

* videoout: render blank frame when video output is closed

required to render imgui even when game has no video output

- fixed merge compile-error

src/imgui/renderer/imgui_impl_vulkan.h

@@ -0,0 +1,43 @@
+// SPDX-FileCopyrightText: Copyright 2024 shadPS4 Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+// Based on imgui_impl_vulkan.h from Dear ImGui repository
+
+#pragma once
+
+#define VULKAN_HPP_NO_EXCEPTIONS
+#include "video_core/renderer_vulkan/vk_common.h"
+
+struct ImDrawData;
+
+namespace ImGui::Vulkan {
+
+struct InitInfo {
+    vk::Instance instance;
+    vk::PhysicalDevice physical_device;
+    vk::Device device;
+    uint32_t queue_family;
+    vk::Queue queue;
+    uint32_t image_count;               // >= 2
+    vk::DeviceSize min_allocation_size; // Minimum allocation size
+    vk::PipelineCache pipeline_cache;
+    uint32_t subpass;
+    vk::PipelineRenderingCreateInfoKHR pipeline_rendering_create_info;
+
+    // (Optional) Allocation, Logging
+    const vk::AllocationCallbacks* allocator{};
+    void (*check_vk_result_fn)(vk::Result err);
+};
+
+vk::DescriptorSet AddTexture(vk::Sampler sampler, vk::ImageView image_view,
+                             vk::ImageLayout image_layout);
+
+void RemoveTexture(vk::DescriptorSet descriptor_set);
+
+bool Init(InitInfo info);
+void Shutdown();
+void NewFrame();
+void RenderDrawData(ImDrawData& draw_data, vk::CommandBuffer command_buffer,
+                    vk::Pipeline pipeline = VK_NULL_HANDLE);
+
+} // namespace ImGui::Vulkan