spike: windows ffmpeg R1 v2 — vcvars (cl.exe) + bash + --toolchain=msvc #2

	# TEMP R1 spike v2: FFmpeg configure on windows with a PROPER MSVC dev env
	# (cl.exe on PATH via vcvars) + Git Bash + ffmpeg's documented --toolchain=msvc.
	name: snapshot-windows-ffmpeg
	on:
	push:
	branches: ['spike/ffmpeg-windows']
	workflow_dispatch:
	jobs:
	capture:
	runs-on: windows-latest
	timeout-minutes: 40
	steps:
	- uses: ilammy/msvc-dev-cmd@v1 # exports MSVC env (cl.exe/link.exe on PATH) to later steps
	- name: Fetch + configure (msvc) + make -n
	shell: bash
	run: \|
	echo "cl.exe: $(which cl.exe 2>/dev/null \|\| echo MISSING)"
	curl -L -fsS -o ffmpeg.tar.gz "https://ffmpeg.org/releases/ffmpeg-8.1.2.tar.gz"
	tar -xzf ffmpeg.tar.gz
	mkdir build && cd build
	# ffmpeg's MSVC path: cl.exe as cc; needs a couple of shims for the bash env
	../ffmpeg-8.1.2/configure --toolchain=msvc --disable-autodetect --disable-programs --disable-doc >cfg.log 2>&1 && echo "CONFIGURE-MSVC OK" \|\| { echo "=== configure FAILED, tail ==="; tail -40 cfg.log; }
	if [ -f config.h ]; then
	echo "=== windows config.h facts ==="
	grep -E '#define (OS_NAME\|ARCH_X86_64\|EXTERN_PREFIX\|SLIBSUF\|HAVE_W32THREADS\|HAVE_PTHREADS\|HAVE_MMX\|HAVE_ALIGNED_MALLOC\|HAVE_WINDOWS_H\|HAVE_INLINE_ASM)' config.h
	make -n >make-n.log 2>/dev/null \|\| true
	echo ".c=$(grep -oE '[^ ]+\.c\b' make-n.log\|sort -u\|wc -l) .S=$(grep -oE '[^ ]+\.S\b' make-n.log\|sort -u\|wc -l) .asm=$(grep -oE '[^ ]+\.asm\b' make-n.log\|sort -u\|wc -l)"
	echo "CONFIGURE SUCCEEDED — R1 configure step is achievable on windows"
	else
	echo "R1: windows configure still blocked"; exit 1
	fi

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