Add new packages and build scripts for various libraries

- Added Nuklear GUI library with build script and configuration.
- Introduced OpenH264 encoder/decoder with build configuration.
- Added PortAudio library for audio I/O with custom build script.
- Included Python Execnet for multi-Python deployment.
- Added Pytest Xdist plugin for distributed testing.
- Introduced Shaderc for shader compilation tools.
- Added Snappy compression library with necessary patches and configuration.
- Included SoundTouch audio processing library with build configuration.
- Added SRT library for secure reliable transport.
- Introduced VapourSynth video processing framework with configuration.
- Added Vid.stab for video stabilization.
- Included WebRTC Audio Processing library with build configuration.
- Added X264 video encoding library with patches for POSIX compliance.
- Introduced X265 video encoder with build configuration.
- Added XKeyboard Config for X keyboard configuration files.
- Included Xorg XKBComp for keyboard description compilation.
- Added Xvidcore MPEG-4 video codec library with configuration.
- Introduced ZeroMQ messaging system with patches and build configuration.
- Added Zimg library for scaling and colorspace conversion.

extra/cunit/cunit.toml

@@ -0,0 +1,30 @@
+[build]
+type = "autotools"
+
+[build.flags]
+configure = [
+    "--enable-automated",
+    "--enable-basic",
+    "--enable-console",
+    "--enable-test",
+    "--enable-shared",
+    "--disable-static",
+]
+post_install = [ 'rm -r "$DESTDIR/usr/share/CUnit"', 'mv "$DESTDIR/usr/doc" "$DESTDIR/usr/share/"' ]
+
+
+[dependencies]
+runtime = ["glibc"]
+
+[package]
+description = "Unit Testing Framework for C"
+homepage = "http://cunit.sourceforge.net/"
+license = "LGPL-2.1-or-Later"
+name = "cunit"
+version = "2.1.3"
+
+[[source]]
+extract_dir = "$name-$version"
+sha256 = "f5b29137f845bb08b77ec60584fdb728b4e58f1023e6f249a464efa49a40f214"
+url = "https://downloads.sourceforge.net/project/cunit/CUnit/2.1-3/CUnit-2.1-3.tar.bz2"
+post_extract = [ "autoreconf -fiv" ]