added local files for imgui

Author: Hardcode3

external/imgui/LICENSE.txt

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014-2023 Omar Cornut
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

external/imgui/backends/imgui_impl_glfw.cpp

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+// dear imgui: Platform Backend for GLFW
+// This needs to be used along with a Renderer (e.g. OpenGL3, Vulkan, WebGPU..)
+// (Info: GLFW is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
+// (Requires: GLFW 3.1+. Prefer GLFW 3.3+ for full feature support.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLFW_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [x] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange' (note: the resizing cursors requires GLFW 3.4+).
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+
+// Issues:
+//  [ ] Platform: Multi-viewport support: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
+// Read online: https://github.com/ocornut/imgui/tree/master/docs
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+
+struct GLFWwindow;
+struct GLFWmonitor;
+
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOpenGL(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOther(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplGlfw_NewFrame();
+
+// GLFW callbacks (installer)
+// - When calling Init with 'install_callbacks=true': ImGui_ImplGlfw_InstallCallbacks() is called. GLFW callbacks will be installed for you. They will chain-call user's previously installed callbacks, if any.
+// - When calling Init with 'install_callbacks=false': GLFW callbacks won't be installed. You will need to call individual function yourself from your own GLFW callbacks.
+IMGUI_IMPL_API void     ImGui_ImplGlfw_InstallCallbacks(GLFWwindow* window);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_RestoreCallbacks(GLFWwindow* window);
+
+// GLFW callbacks (individual callbacks to call if you didn't install callbacks)
+IMGUI_IMPL_API void     ImGui_ImplGlfw_WindowFocusCallback(GLFWwindow* window, int focused);        // Since 1.84
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CursorEnterCallback(GLFWwindow* window, int entered);        // Since 1.84
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CursorPosCallback(GLFWwindow* window, double x, double y);   // Since 1.87
+IMGUI_IMPL_API void     ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CharCallback(GLFWwindow* window, unsigned int c);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_MonitorCallback(GLFWmonitor* monitor, int event);