Default both build scripts to orcacad-deps, not the other fork's image

Both scripts defaulted IMAGE to snaporca-deps. That image is Snapmaker-based
and lacks Eigen 5.0.1, CGAL 5.6.3, wx 3.3.2 and Python 3.12 Development.Embed,
so running either script here without an explicit IMAGE= dies at CMake
configure — which is a large part of why this fork reached M8 having never once
compiled (1633005bba). The volume defaults were fixed in that commit; the image
default was missed in both files.

docker-iter-build.sh also never mounted deps_src, so it could not have
configured even with the right image: root CMakeLists.txt:947 FATAL_ERRORs
when deps_src/pybind11/include/pybind11/pybind11.h is absent, and
src/CMakeLists.txt pulls semver/hints/imgui/imguizmo/hidapi from the same tree.
kernel-test.sh got that mount in 1633005bba; this is the same fix for the GUI
build path, needed before the Phase B GUI work can be ported here.

CadDocument.hpp: mate_kind comment, mirrored verbatim from snaporca dbaa104f62
so the header stays byte-identical across forks.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

scripts/kernel-test.sh

@@ -22,7 +22,11 @@
 set -euo pipefail
 
 REPO="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
-IMAGE="${IMAGE:-snaporca-deps}"
+# orcacad-deps, NOT snaporca-deps: this fork is mainline-based and needs Eigen 5.0.1,
+# CGAL 5.6.3, wx 3.3.2 and Python 3.12 Development.Embed, none of which snaporca-deps has.
+# With the wrong image CMake dies at configure, which is exactly why this fork went
+# M1-M8 without ever compiling (see commit 1633005bba).
+IMAGE="${IMAGE:-orcacad-deps}"
 # Must NOT default to snaporca_buildcache: that is the other fork's volume, and pointing
 # this fork at it makes the two silently trade build artefacts. docker-iter-build.sh had the
 # identical defect and was fixed to orcacad_buildcache; this script was missed.