use libevent 2.1.12 on windows

[mercury233]

Since version 2.1.12 uses if_nametoindex, which is a function available starting from Windows Vista, it cannot support Windows XP.

[purerosefallen]

Can it not be a draft?
I wish the whole build system using one version of libevent.

[Copilot]

Pull Request Overview

This PR updates the build configuration to use libevent 2.1.12 on Windows, adds version detection/warnings in the Premake script, links the new iphlpapi library in the gframe project, and updates the GitHub Actions workflow to download and extract the 2.1.12 release.

• Introduce EVENT_VERSION parsing and warnings for unsupported versions or Windows XP.
• Conditionally include evutil_time.c and adjust Windows prebuild commands/defines for libevent 2.1.
• Update gframe’s Premake to link iphlpapi and change CI workflow to pull libevent 2.1.12.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
premake/event/premake5.lua	Add version parsing, warnings, conditional file inclusion, and Windows-specific defines/prebuild commands
gframe/premake5.lua	Link iphlpapi alongside ws2_32
.github/workflows/build.yml	Point to libevent 2.1.12 release tarball and adjust extraction path

Comments suppressed due to low confidence (1)

premake/event/premake5.lua:32

• The path segment \\nmake may be misinterpreted or produce an incorrect directory name. Also, this single command copies two different source folders into one target. Split into two clear commands and verify the folder name is correct (e.g., ..\\event\\WIN32-Code\\nmake).

prebuildcommands { "xcopy /E /Y $(ProjectDir)..\\event\\WIN32-Code\\nmake $(ProjectDir)..\\event\\include" }

[purerosefallen]

anything left?