refactor!: repo cleanup (#2650)

- Move cmake files to dedicated cmake folder
- Move scattered python files to `scripts/` folder
- Update CMakeLists.txt to reflect changes
* feat(scripts): add README to folder

cmake/imgui.cmake

@@ -0,0 +1,28 @@
+include(FetchContent)
+FetchContent_Declare(
+    imgui
+    GIT_REPOSITORY https://github.com/ocornut/imgui.git
+    GIT_TAG        v1.90
+    GIT_PROGRESS TRUE
+)
+message("ImGui")
+FetchContent_GetProperties(imgui)
+if(NOT imgui_POPULATED)
+    FetchContent_Populate(imgui)
+
+    file(GLOB SRC_IMGUI
+        "${imgui_SOURCE_DIR}/*.cpp"
+        "${imgui_SOURCE_DIR}/backends/imgui_impl_win32.cpp"
+        "${imgui_SOURCE_DIR}/backends/imgui_impl_dx11.cpp"
+        "${imgui_SOURCE_DIR}/misc/cpp/imgui_stdlib.cpp"
+    )
+
+    add_library(imgui STATIC ${SRC_IMGUI} )
+    source_group(TREE ${imgui_SOURCE_DIR} PREFIX "imgui" FILES ${SRC_IMGUI})
+    target_include_directories(imgui PRIVATE
+        "${imgui_SOURCE_DIR}"
+        "${imgui_SOURCE_DIR}/backends"
+        "${imgui_SOURCE_DIR}/misc/cpp"
+    )
+endif()
+set_property(TARGET imgui PROPERTY CXX_STANDARD 23)