Add option in the controller config to set where static assets are
loaded from in order to support deployments where the static assets are
server via a CDN while the API is directly accessed.
This is useful because some CDNs put low limits on how large requests
bodies can be, which causes issues with uploading large mods and saves.
An instance's factorio.version can now target a release channel such as
"stable" or "experimental" (any key from factorio.com/api/latest-releases)
in addition to "latest" and specific X.Y / X.Y.Z versions.
The controller proxies the latest-releases API through a ValueCache and
persists the last successful response to latest-releases.json, serving that
copy when the API is unreachable. On instance start the host resolves a
channel to the concrete version it points to and feeds it into the existing
checkForUpdates/findVersion path, so a channel auto-installs and runs like a
pinned version. The version selector in the web UI lists the available
channels alongside "latest".
Also clarifies the host log/error when a newer version cannot be downloaded
automatically because the host uses a direct (single-version) Factorio
install rather than a versioned directory.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Hornwitser