Build offline OpenPrestige release bundles

Rename the injector and package it with an embedded payload for Windows, Linux, and macOS x64/ARM64. Add a core-only ImGui native build, multi-platform CI and release packaging, and shared per-user storage with legacy config migration.

scripts/imgui-core/CMakeLists.txt

@@ -0,0 +1,58 @@
+cmake_minimum_required(VERSION 3.20)
+project(openprestige_imgui LANGUAGES CXX)
+
+file(GLOB GENERATED CONFIGURE_DEPENDS "${CORE_JNI_DIR}/imgui_*.cpp")
+add_library(imgui-java64 SHARED
+    ${GENERATED}
+    "${CORE_JNI_DIR}/imgui.cpp"
+    "${CORE_JNI_DIR}/imgui_draw.cpp"
+    "${CORE_JNI_DIR}/imgui_tables.cpp"
+    "${CORE_JNI_DIR}/imgui_widgets.cpp"
+    "${CORE_JNI_DIR}/imgui_demo.cpp"
+    "${CORE_JNI_DIR}/jni_jvm.cpp"
+    "${CORE_JNI_DIR}/jni_common.cpp"
+    "${CORE_JNI_DIR}/jni_binding_struct.cpp"
+    "${CORE_JNI_DIR}/jni_callbacks.cpp"
+    "${CORE_JNI_DIR}/jni_assertion.cpp"
+    "${CORE_JNI_DIR}/jni_internal.cpp"
+)
+target_compile_features(imgui-java64 PRIVATE cxx_std_17)
+if(WIN32)
+    set(JNI_OS win32)
+elseif(APPLE)
+    set(JNI_OS mac)
+else()
+    set(JNI_OS linux)
+endif()
+target_include_directories(imgui-java64 PRIVATE
+    "${CORE_JNI_DIR}"
+    "${CORE_JNI_DIR}/jni-headers"
+    "${CORE_JNI_DIR}/jni-headers/${JNI_OS}"
+)
+target_compile_definitions(imgui-java64 PRIVATE IMGUI_DISABLE_DEMO_WINDOWS)
+set_target_properties(imgui-java64 PROPERTIES
+    CXX_VISIBILITY_PRESET hidden
+    VISIBILITY_INLINES_HIDDEN YES
+    MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>"
+    LIBRARY_OUTPUT_DIRECTORY "${CORE_OUTPUT_DIR}"
+    RUNTIME_OUTPUT_DIRECTORY "${CORE_OUTPUT_DIR}"
+    RUNTIME_OUTPUT_DIRECTORY_RELEASE "${CORE_OUTPUT_DIR}"
+)
+if(MSVC)
+    target_compile_options(imgui-java64 PRIVATE /O1 /Gy /GL /utf-8)
+    target_link_options(imgui-java64 PRIVATE /LTCG /OPT:REF /OPT:ICF)
+else()
+    target_compile_options(imgui-java64 PRIVATE -Os -ffunction-sections -fdata-sections)
+    if(APPLE)
+        target_link_options(imgui-java64 PRIVATE -Wl,-dead_strip)
+    else()
+        target_link_options(imgui-java64 PRIVATE -Wl,--gc-sections -s)
+    endif()
+    if(MINGW)
+        target_link_options(imgui-java64 PRIVATE -static-libgcc -static-libstdc++)
+    endif()
+endif()
+if(WIN32)
+    set_target_properties(imgui-java64 PROPERTIES PREFIX "")
+    target_link_libraries(imgui-java64 PRIVATE imm32 user32)
+endif()