ci: add release-gentoo workflow for overlay auto-update

Triggered by release-linux completion (same as AUR).
Updates ebuilds in vicrodh/qbz-overlay with new version.
Requires OVERLAY_PAT secret for cross-repo push.

cc

packaging/gentoo/qbz-bin.ebuild.template

@@ -0,0 +1,68 @@
+# Copyright 2024-2026 Gentoo Authors
+# Distributed under the terms of the MIT License
+
+EAPI=8
+
+DESCRIPTION="Native hi-fi Qobuz desktop player for Linux (prebuilt binary)"
+HOMEPAGE="https://qbz.lol https://github.com/vicrodh/qbz"
+
+MY_PV="${PV}"
+SRC_URI="
+	amd64? ( https://github.com/vicrodh/qbz/releases/download/v${MY_PV}/qbz_${MY_PV}_amd64.tar.gz )
+	arm64? ( https://github.com/vicrodh/qbz/releases/download/v${MY_PV}/qbz_${MY_PV}_aarch64.tar.gz )
+"
+
+LICENSE="MIT"
+SLOT="0"
+KEYWORDS="~amd64 ~arm64"
+
+RDEPEND="
+	net-libs/webkit-gtk:4.1
+	x11-libs/gtk+:3
+	media-libs/alsa-lib
+	dev-libs/openssl
+	dev-libs/libappindicator:3
+	x11-libs/libxkbcommon
+"
+
+BDEPEND=""
+
+# Binary package, no compilation needed
+QA_PREBUILT="usr/bin/qbz"
+
+S="${WORKDIR}"
+
+src_unpack() {
+	default
+	# Tarball extracts to qbz_${PV}_${arch}/ directory
+	if use amd64; then
+		S="${WORKDIR}/qbz_${MY_PV}_amd64"
+	elif use arm64; then
+		S="${WORKDIR}/qbz_${MY_PV}_aarch64"
+	fi
+}
+
+src_install() {
+	dobin qbz
+
+	insinto /usr/share/applications
+	newins qbz.desktop qbz.desktop
+
+	local size
+	for size in 32 48 64 128 256; do
+		if [[ -f "icons/hicolor/${size}x${size}/apps/qbz.png" ]]; then
+			insinto "/usr/share/icons/hicolor/${size}x${size}/apps"
+			doins "icons/hicolor/${size}x${size}/apps/qbz.png"
+		fi
+	done
+}
+
+pkg_postinst() {
+	xdg_icon_cache_update
+	xdg_desktop_database_update
+}
+
+pkg_postrm() {
+	xdg_icon_cache_update
+	xdg_desktop_database_update
+}