The daemon moves to its own repo (XC_VM_Fanout, GIT_REPO_FANOUT) that ships
per-arch static binaries as GitHub Release assets. Since we're fully
migrating onto the daemon, the panel needs to fetch and update it.
- FanoutBinaryCommand (`console.php fanout_binary`): reads the installed
version straight from the binary (`xc_fanout -version`), compares to the
latest release, and when they differ downloads the arch-matched asset,
verifies its SHA-256 against the release SHA256SUMS, installs it
atomically and restarts the daemon (the service keepalive respawns it).
`force` reinstalls the current version. Modelled on BinariesCommand.
- GIT_REPO_FANOUT constant.
- docs/xc_fanout.md: separate-repo + install/update section.
The daemon repo itself (source + release.sh + a v* release GitHub Action,
binaries gitignored) is prepared under XC_VM_Fanout/ for the user to push.
Plain-language companion to the ADRs: the worker-per-viewer problem it
solves, what it does (and doesn't), and the client/control surfaces PHP
uses (FanoutClient, X-Accel routes, fanout_sync).
Divarion_D