[libevent, pistache] Update pistache to 0.4.25.

[Billy O'Neal (BillyONeal)]

See also #43852

The version of Pistache we were shipping does not build on Ubuntu 26.04 "Resolute Raccoon". Rather than try to patch around the problem, we should not be trying to ship 6 year old copies.

Unlike the previous attempt I'm not going to try adding features and controls, just bringing forward what was supported before. This is not a statement against those features, I'm just trying to do the minimal update to make Resolute work.

Also fixed libevent's pkg-config bindings to make debug builds work.

• Changes comply with the maintainer guide.
• SHA512s are updated for each updated download.
• The "supports" clause reflects platforms that may be fixed by this new version, or no changes were necessary.
• Any fixed CI baseline and CI feature baseline entries are removed from that file, or no entries needed to be changed.
• All patch files in the port are applied and succeed.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Exactly one version is added in each modified versions file.

[Billy O'Neal (BillyONeal)]

GPT 5.6 Sol notes:

• Prevent the Windows build/install from running upstream's event-log installation scripts. The current build writes under C:\Program Files, invokes wevtutil, and creates an HKCU registry key. vcpkg ports must not modify the host system. Patch or configure the upstream build so these targets/install scripts are disabled while retaining any resource DLL that is legitimately part of the package.
• Fix the Windows dynamic-library naming mismatch. Release and Debug consumers link successfully, but their executables import pistache.dll; the package only contains pistache-0.4.dll, so both pkg-config and direct-link examples terminate with STATUS_DLL_NOT_FOUND. The import library and installed DLL must use the same name.
• Static Libevent pkg-config consumers still fail because libevent.pc omits iphlpapi, leaving if_nametoindex unresolved. This issue predates the PR; the new rewrite correctly changes Debug library names but does not affect the system-library list.

[Billy O'Neal (BillyONeal)]

pistacheio/pistache#1355

[Mahmoud Saleh (MahmoudGSaleh)]

Is this accurate? The GitHub readme says it supports Windows. It does not Android though.

Pistache supports Linux, macOS, Windows and BSD (FreeBSD, OpenBSD, and NetBSD). To use in macOS, Windows, or BSD, see the respective files: Building on macOS.txt, Building on Windows.txt or Building on BSD.txt.

[Billy O'Neal (BillyONeal)]

Upstream claims to support Windows but their meson build system does not produce usable results, that's why I filed pistacheio/pistache#1355

This is still an improvement vs. the status quo because the previous port only supported Linux