Add dev-qt from an older version of the gentoo repo

Qt5 has been removed, we restore it since we still use it.

dev-qt/qtscxml/qtscxml-6.8.3.ebuild

@@ -0,0 +1,34 @@
+# Copyright 2021-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit qt6-build
+
+DESCRIPTION="State Chart XML (SCXML) support library for the Qt6 framework"
+
+if [[ ${QT6_BUILD_TYPE} == release ]]; then
+	KEYWORDS="amd64 arm arm64 ~loong ~ppc ppc64 ~riscv x86"
+fi
+
+IUSE="qml"
+
+RDEPEND="
+	~dev-qt/qtbase-${PV}:6[gui]
+	qml? ( ~dev-qt/qtdeclarative-${PV}:6 )
+"
+DEPEND="${RDEPEND}"
+
+CMAKE_SKIP_TESTS=(
+	# may fail with pid-sandbox, or at least musl/hardened+gcc (exact
+	# conditions unknown but passes without pid, considering this flaky)
+	tst_qstatemachine
+)
+
+src_configure() {
+	local mycmakeargs=(
+		$(cmake_use_find_package qml Qt6Qml)
+	)
+
+	qt6-build_src_configure
+}