CAD engine source for VIEW3D

occt-import-js 0.0.23, commit c2148e54b456b571238d35cac037d304053d64b2.
Upstream: https://github.com/kovacsv/occt-import-js/tree/0.0.23
OCCT submodule commit d2abb6d844231cb8f29be6894440874a4700e4a5.
Upstream: https://github.com/Open-Cascade-SAS/OCCT/tree/d2abb6d844231cb8f29be6894440874a4700e4a5
The distributed CAD engine JavaScript and WASM are unmodified upstream binaries; filenames are renamed.
Unpack cad-import-source.tar.gz. Unpack cad-kernel-source.tar.gz and put its contents in the import source's occt directory. Follow the included README and tools build instructions. The engine is served separately at /cad/cad-core.js and /cad/cad-core.wasm. Modified builds can replace these resources in a locally hosted copy. VIEW3D places no additional restrictions on modification or debugging of these library components; their licenses govern those rights.