Packages carry their ONNX Runtime; a DEB per Ubuntu LTS

ONNX Runtime stamps its symbols with each release's version, so the
1.0.0 RPM demanded Fedora 42's exact runtime (issue #5) and the Arch
package would break on the next update. The RPM and the Arch package
now bundle Microsoft's 1.21.0 build, as the DEB does, and the images
test against it. The RPM builds on Fedora 43. A DEB built on Ubuntu
26.04 joins 24.04's, and ubuntu.sh picks by codename.

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile.dev

@@ -1,11 +1,12 @@
-FROM ubuntu:24.04
+ARG BASE=ubuntu:24.04
+FROM $BASE
 ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && apt-get install -y --no-install-recommends \
         g++ cmake ninja-build qt6-base-dev libgl1-mesa-dev qt6-wayland fonts-dejavu-core \
         qt6-image-formats-plugins libheif-dev libheif-plugin-libde265 libfontconfig-dev \
         ca-certificates curl dpkg-dev file fakeroot \
     && rm -rf /var/lib/apt/lists/*
-# Ubuntu 24.04 packages no ONNX Runtime: Microsoft's own build.
+# The ONNX Runtime the packages carry: Microsoft's own build.
 RUN curl -fsSL -o /tmp/ort.tgz \
         https://github.com/microsoft/onnxruntime/releases/download/v1.21.0/onnxruntime-linux-x64-1.21.0.tgz \
     && echo "7485c7e7aac6501b27e353dcbe068e45c61ab51fbaf598d13970dfae669d20bf  /tmp/ort.tgz" | sha256sum -c - \