Group A: source upstream binaries instead of self-built artifacts

The AUR does not allow packages to ship a binary tarball built by the
maintainer - a -bin package must repackage a deliverable published by
upstream. These six packages now do that:

  snapx-bin            upstream's self-contained Linux tar.zst
  zapzap-bin           upstream's pure-Python wheel
  faugus-launcher-bin  upstream's arch-independent .deb
  wiiudownloader-bin   upstream's AppImage
  waydroid-helper-bin  upstream's AppImage
  chiaki-ng-bin        upstream's AppImage

All six drop build_artifact() and switch to refresh_checksums(), so CI no
longer builds or hosts anything - it only tracks upstream's assets.

Where the asset name carries build metadata that does not follow from
pkgver (snapx, faugus-launcher), refresh_checksums() resolves it via the
GitHub API and syncs an _asset variable in the PKGBUILD.

Dependency lists are re-derived from what the bundles actually resolve
outside themselves; the AppImage payloads land in /opt with wrappers in
/usr/bin, because their entry points resolve paths relative to argv[0].

faugus-launcher-bin/pkg.sh

@@ -1,54 +1,34 @@
-# faugus-launcher-bin - prebuilt package of https://github.com/Faugus/faugus-launcher
-# (GTK4 game launcher for running Windows games through UMU-Launcher, Python).
+# faugus-launcher-bin - Faugus Launcher
+# (https://github.com/Faugus/faugus-launcher), a GTK4 front-end for running
+# Windows games through UMU-Launcher.
 #
-# Upstream ships AppImage/deb/rpm but no Arch-friendly binary, so
-# build_artifact() builds the meson project from the release tarball.
+# Upstream publishes an architecture-independent .deb per release, which the
+# PKGBUILD repackages. The Debian revision in the asset name is not derived
+# from the version, so refresh_checksums() resolves the asset via the GitHub
+# API and syncs the _asset variable in the PKGBUILD along with the checksum.
+#
+# Upstream tags carry no "v" prefix.
 
 UPSTREAM_REPO="Faugus/faugus-launcher"
 
-# Installed in CI (pacman) before build_artifact runs.
-# (Translations ship as prebuilt .mo files, so no gettext needed.)
-BUILD_DEPS=(meson ninja python)
-
 latest_version() {
   gh api "repos/$UPSTREAM_REPO/releases/latest" --jq '.tag_name' | sed 's/^v//'
 }
 
-# build_artifact <version> <output-file>
-build_artifact() {
-  local ver="$1" outfile="$2"
-  local workdir destdir srctree sitedir
-  workdir="$(mktemp -d)"
-  destdir="$(mktemp -d)"
+# refresh_checksums <version> <pkgbuild-path>
+refresh_checksums() {
+  local ver="$1" pkgbuild="$2"
+  local asset sha
 
-  curl -sfL "https://github.com/$UPSTREAM_REPO/archive/refs/tags/$ver.tar.gz" | tar -xz -C "$workdir"
-  srctree="$workdir/faugus-launcher-$ver"
+  asset="$(gh api "repos/$UPSTREAM_REPO/releases/tags/$ver" --jq '.assets[].name' \
+    | grep -E "^faugus-launcher_${ver}-[0-9]+_all\.deb$")"
+  [[ "$(wc -l <<< "$asset")" -eq 1 ]] || { echo "expected exactly one deb, got: $asset" >&2; return 1; }
 
-  meson setup "$workdir/build" "$srctree" --prefix=/usr --buildtype=release
-  meson install -C "$workdir/build" --destdir "$destdir"
+  sha="$(curl -sfL "https://github.com/$UPSTREAM_REPO/releases/download/$ver/$asset" \
+    | sha256sum | cut -d' ' -f1)"
 
-  # meson installs the python modules into site-packages, whose path changes
-  # with every Python minor bump and would silently break a prebuilt package.
-  # Relocate to a fixed dir and put it on the launcher's PYTHONPATH (the
-  # launcher script already appends any pre-set PYTHONPATH to its own).
-  sitedir="$(find "$destdir/usr/lib" -maxdepth 2 -type d -name site-packages)"
-  [[ -d "$sitedir/faugus" ]] || { echo "faugus module not found in $sitedir" >&2; return 1; }
-  mkdir -p "$destdir/usr/lib/faugus-launcher"
-  mv "$sitedir/faugus" "$destdir/usr/lib/faugus-launcher/"
-  rm -rf "$destdir/usr/lib/python"*
-
-  head -1 "$destdir/usr/bin/faugus-launcher" | grep -qx '#!/bin/sh' \
-    || { echo "unexpected launcher script format" >&2; return 1; }
-  sed -i '1a export PYTHONPATH="/usr/lib/faugus-launcher${PYTHONPATH:+:$PYTHONPATH}"' \
-    "$destdir/usr/bin/faugus-launcher"
-
-  # These caches are generated by pacman hooks; shipping them would cause
-  # file conflicts on install.
-  rm -f "$destdir/usr/share/applications/mimeinfo.cache" \
-        "$destdir/usr/share/icons/hicolor/icon-theme.cache"
-
-  tar --zstd --sort=name --owner=0 --group=0 --numeric-owner --mtime='@0' \
-      -cf "$outfile" -C "$destdir" usr
-
-  rm -rf "$workdir" "$destdir"
+  sed -i \
+    -e "s|^_asset=.*|_asset=\"$asset\"|" \
+    -e "s|^sha256sums=.*|sha256sums=('$sha')|" \
+    "$pkgbuild"
 }