Integrate G15 submodules with Debian 13 packaging and devcontainer

packaging/Dockerfile

@@ -0,0 +1,8 @@
+FROM debian:trixie-slim
+ENV DEBIAN_FRONTEND=noninteractive
+RUN printf 'deb-src http://deb.debian.org/debian trixie main\n' > /etc/apt/sources.list.d/g15-source.list \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends build-essential autoconf automake libtool pkg-config debhelper dpkg-dev libusb-1.0-0-dev git ca-certificates fakeroot lintian devscripts dh-sequence-movetousr libfreetype-dev libxtst-dev quilt shellcheck \
+    && rm -rf /var/lib/apt/lists/*
+WORKDIR /work
+CMD ["bash", "packaging/container-build.sh"]