The Windows analogue of scripts/ci/setup-macos-runner.sh: downloads act_runner (gitea-runner)
in host mode, bumps Node 20 via nvm4w (actions/checkout@v4), registers against git.unom.io with
labels windows-amd64:host, and installs a SYSTEM scheduled task that keeps the daemon alive
across reboots. The daemon's env wrapper hard-codes this box's MSVC/WinUI toolchain (cargo/rustup,
NASM, CMake, LLVM, FFmpeg, the ASCII CARGO_HOME SDL3's PCH needs) so the Windows workflow inherits
a working toolchain. Idempotent; token (from org unom -> Settings -> Actions -> Runners) not
persisted.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
