FFmpeg in the official scrcpy 4.1 Windows x64 backend

SUN Stream does not claim ownership of FFmpeg.
Version reported by av_version_info(): 8.1.2
License reported by all four FFmpeg libraries: LGPL version 2.1 or later.
Project and licensing guidance: https://ffmpeg.org/legal.html
Source archive: https://ffmpeg.org/releases/ffmpeg-8.1.2.tar.xz
Source SHA256: 464BEB5E7BF0C311E68B45AE2F04E9CC2AF88851ABB4082231742A74D97B524C
Source sidecar: third-party-sources/ffmpeg-8.1.2.tar.xz beside the built MSI.

Original binary archive: scrcpy-win64-v4.1.zip
SHA256: 5B12172B3264B2889F4583EE64752CE832E29BC8B1089DCA81093459697165DB
Upstream build recipe: https://github.com/Genymobile/scrcpy/blob/v4.1/app/deps/ffmpeg.sh
avcodec-62.dll SHA256: 7179DE2B132E78EB0A76458A0A3859DFE1EDCBB6D2EEB4A456F03F7AE96D5B66

Configuration reported by the actual DLLs:
--prefix=/home/runner/work/scrcpy/scrcpy/app/deps/work/install/win64-cross-shared --pkg-config-flags=--static --extra-cflags='-O2 -fPIC' --disable-programs --disable-doc --disable-swscale --disable-avfilter --disable-network --disable-everything --disable-vulkan --disable-vaapi --disable-vdpau --enable-swresample --enable-libdav1d --enable-decoder=h264 --enable-decoder=hevc --enable-decoder=av1 --enable-decoder=vp8 --enable-decoder=vp9 --enable-decoder=libdav1d --enable-decoder=pcm_s16le --enable-decoder=opus --enable-decoder=aac --enable-decoder=flac --enable-decoder=png --enable-protocol=file --enable-demuxer=image2 --enable-parser=png --enable-zlib --enable-muxer=matroska --enable-muxer=mp4 --enable-muxer=opus --enable-muxer=flac --enable-muxer=wav --disable-avdevice --disable-static --enable-shared --enable-cross-compile --cross-prefix=x86_64-w64-mingw32- --cc=x86_64-w64-mingw32-gcc --target-os=mingw32 --arch=x86_64

Audit limitation: version/configuration match the upstream recipe. Exact build
reproduction, incorporated dependency source/notices, and public source delivery
remain open. This file is not a legal-compliance approval. No source is hosted
or release published by the installer build script.
