fix(steps-guix): add cmake bootstrap build and libgit2 cmake-based build steps

steps-guix/cmake-4.2.3/pass1.sh

@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+src_prepare() {
+    default
+}
+
+src_configure() {
+    ./bootstrap \
+        --prefix="${PREFIX}" \
+        --parallel="${JOBS}" \
+        --no-qt-gui \
+        -- \
+        -DCMAKE_BUILD_TYPE=Release \
+        -DCMAKE_USE_OPENSSL=ON \
+        -DCMAKE_INSTALL_LIBDIR="${LIBDIR}"
+}
+
+src_compile() {
+    make "${MAKEJOBS}"
+}
+
+src_install() {
+    make install DESTDIR="${DESTDIR}"
+}

steps-guix/cmake-4.2.3/sources

@@ -0,0 +1 @@
+f https://github.com/Kitware/CMake/releases/download/v4.2.3/cmake-4.2.3.tar.gz 7efaccde8c5a6b2968bad6ce0fe60e19b6e10701a12fce948c2bf79bac8a11e9