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/liblc3/liblc3.toml

@@ -0,0 +1,28 @@
+[build]
+type = "meson"
+
+[build.flags]
+build_dir = "build"
+configure = [
+    "-Dpython=true",
+    "-Dtools=true",
+]
+
+[dependencies]
+build = [
+    "meson",
+    "python",
+]
+optional = ["python"]
+runtime = ["glibc"]
+
+[package]
+description = "Low Complexity Communication Codec library and tools"
+homepage = "https://github.com/google/liblc3"
+license = "Apache-2.0"
+name = "liblc3"
+version = "1.1.3"
+
+[[source]]
+extract_dir = "$name-$version"
+url = "https://github.com/google/liblc3.git#v$version"