Linux builds missing from update manifest (updates.openlogi.org) — in-app updater can never detect updates on Linux

[Addonis-13]

OpenLogi version
0.8.3

Operating system
Linux (Ubuntu, installed via .deb from GitHub Releases)

Description
check_for_updates / auto_install_updates are enabled by default, but the app never finds updates on Linux. Root cause: the updater queries https://updates.openlogi.org/channels/stable/latest.json for update checks.

Fetching that manifest directly shows it only lists "macos" and "windows" asset entries — no "linux" entry at all — even though the matching GitHub Release (v0.8.3) does publish a linux .deb (openlogi-v0.8.3-linux-amd64.deb).

So the in-app updater can never detect or install updates on Linux, regardless of local config, because the release pipeline apparently doesn't push Linux build metadata into the update channel manifest, only to GitHub Releases.

Steps to reproduce

1. Install OpenLogi via the Linux .deb
2. Leave check_for_updates/auto_install_updates on (default)
3. Fetch updates.openlogi.org/channels/stable/latest.json and compare its asset list to the GitHub Releases page for the same version

Expected
Linux builds included in the update manifest so the built-in updater actually works on Linux.

[4ni1ak]

This is the same underlying issue as #605 — xtask release latest-json deliberately never lists Linux packages (.deb/.rpm/.pkg.tar.zst) in the update manifest, on purpose: those installs are meant to update through the distro package manager, not the in-app updater. The bug is that the GUI still offers the in-app check/auto-install on Linux with no indication of that, so it just silently never finds anything (or errors on manual check).

#838 already fixes the GUI side: it adds an IN_APP_UPDATES build-time flag, skips the launch-time check and auto-install observer where there's no updatable artifact, and the Settings → Updates page shows the running version + "update via your package manager" instead of a check button that can't do anything on Linux. Still open, unmerged.

The manifest not including Linux assets isn't itself a bug to fix — that's staying intentional per #838's description.

[AprilNEA]

Duplicate of #605: the Linux GUI offers an in-app update check with no supported update artifact.