Add Linux build support with msvc-wine

[fyryNy]

Summary

This PR adds Linux support to the Union plugin template using
mstorsjo/msvc-wine.

The generated plugins still use the real 32-bit MSVC toolchain and produce
Windows-compatible PE32 DLLs.

Changes

• Added Linux configure and build presets for:
  • G1
  • G1A
  • G2
  • G2A
  • MP
  • Debug and Release
• Added a configurable msvc-wine x86 toolchain.
• Added MSVC_WINE_ROOT support through:
  • CMakeUserConfigPresets.json
  • the environment
  • a default $HOME/my_msvc/opt/msvc location
• Added a Wine-compatible linker wrapper.
• Added preset-aware compile_commands.json generation.
• Added direct IntelliSense entries for .ipp sources with the correct:
  • engine
  • Gothic namespace
  • build configuration
  • MSVC and Windows SDK include directories
• Added separate automatically selected VS Code configurations:
  • Linux uses the generated compilation database.
  • Win32 uses the CMake Tools configuration provider.
• Added Linux VDF packaging through Wine.
• Ensured UnionAPI.dll is copied before VDF packaging.
• Added verification that GothicVDFS actually creates a new archive.
• Updated the README with Linux installation, building, packaging, and
  IntelliSense instructions.

Usage

Install msvc-wine and configure its location in
CMakeUserConfigPresets.json:

{
  "name": "msvc-wine-config",
  "hidden": true,
  "cacheVariables": {
    "MSVC_WINE_ROOT": "$env{HOME}/my_msvc/opt/msvc"
  }
}

Then configure and build the required preset:

cmake --fresh --preset G2A-Release-msvc-wine
cmake --build --preset G2A-Release-msvc-wine

Validation

Tested successfully on Linux with:

• G1-Debug-msvc-wine
• G2A-Release-msvc-wine
• MP-Release-msvc-wine

Validation included:

• Successful Debug and Release compilation.
• PE32 Intel i386 plugin and Union API DLLs.
• Correct single-engine source selection.
• Correct four-engine MP compilation.
• Successful VDF generation through Wine.
• VDF containing both UnionPlugin.dll and UnionAPI.dll.
• clangd validation of src/Plugin.ipp with zero errors.
• Correct preset-specific engine definitions and include paths.
• No editor-only IntelliSense targets included in normal builds.

The existing .ipp translation-unit generator was not modified.