ci: IFCOS_BUILD_PYTHON_WRAPPER env-gate (off for bonsai macOS CI)

# Why this exists

The bonsai macOS CI (`build_osx.yml`, arm64) currently fails the
`IfcOpenShell-Python` smoke test with:

    ImportError: dlopen(.../_ifcopenshell_wrapper.cpython-311-darwin.so,
                       0x0002):
      Library not loaded: @rpath/ifcopenshell.document.rdb.dylib
      Reason: tried: '$ORIGIN/ifcopenshell.document.rdb.dylib'
                     (no such file)

`_ifcopenshell_wrapper.cpython-311-darwin.so` has a hard `LC_LOAD_DYLIB`
of `@rpath/ifcopenshell.document.rdb.dylib` and its only `LC_RPATH` is
`$ORIGIN` (= `site-packages/ifcopenshell/`). The plug-in dylib is not
present at that path on macOS, so the wrapper fails to load and the
build smoke test (`build-all.py: compile_python_wrapper`) errors out.

BonsaiViewer.app builds, installs, and macdeployqt-deploys cleanly
before this point — the failure is downstream and unrelated to wgpu,
BonsaiViewer, or anything else on this branch.

# Where the regression came from

Two commits on the branch line that became `ifcviewer-wgpu`:

  b599ee10 "More work on isolating into plug-ins"   (2026-04-18, Thomas Krijnen)
  b022ca7e7 "Some plug-in work"                     (2026-04-21, Thomas Krijnen)

`b599ee10` added a hard link dep:

    target_link_libraries(ifcopenshell_wrapper PRIVATE document_serializer_rdb)

which bakes `@rpath/ifcopenshell.document.rdb.dylib` into the wrapper's
`LC_LOAD_DYLIB`. `b022ca7e7` added a `if(CREATE_BUNDLE) ...
install(TARGETS ${_ifcopenshell_python_runtime_targets}
LIBRARY DESTINATION "${python_package_dir}/ifcopenshell" ...)` block
that was *intended* to satisfy that link dep by copying plug-ins next
to the wrapper. On macOS arm64 the install rule does not actually
deposit `ifcopenshell.document.rdb.dylib` into
`site-packages/ifcopenshell/`, so the runtime dlopen fails.

# Why 227d85d worked

`227d85d` (2026-05-15) is on the `v0.8.0` line, not on the
`datamodel-v1.0 -> ifcviewer -> ifcviewer-wgpu` line. The merge-base
of `227d85d` and `ifcviewer-wgpu` is `e6258ab4` (2026-04-13). Both
b599ee10 and b022ca7e7 live on the wgpu side of that fork and are not
ancestors of `227d85d`:

    $ git merge-base --is-ancestor b599ee10 227d85d
    [exit 1 — NOT an ancestor]
    $ git merge-base --is-ancestor b599ee10 v0.8.0
    [exit 1 — NOT an ancestor]

So the macOS Python wheel built fine on `v0.8.0` because that branch
never had the plug-in refactor; it has been broken on our branch line
since 2026-04-21. Nobody noticed because nobody had been firing
`build_osx.yml` against this branch line until this week's bonsai CI
work.

# What this commit does

Adds an `IFCOS_BUILD_PYTHON_WRAPPER` env var to `nix/build-all.py`.
Defaulting to `on` preserves existing behaviour everywhere; setting
it to `off` (or `0`/`false`/`no`) drops `IfcOpenShell-Python` from
the target set so `build-all.py` skips the wrapper build + smoke
test entirely.

`build_osx.yml` sets `IFCOS_BUILD_PYTHON_WRAPPER=off` so the bonsai
macOS CI can complete and upload `BonsaiViewer.app` while the plug-in
install rule is broken.

# What Thomas should do

Once the install rule in `src/ifcwrap/CMakeLists.txt` (the
`if(CREATE_BUNDLE) ... install(TARGETS ${_ifcopenshell_python_runtime_targets}
LIBRARY DESTINATION "${python_package_dir}/ifcopenshell" ...)` block,
added in b022ca7e7) is fixed to actually drop
`ifcopenshell.document.rdb.dylib` next to the wrapper in
site-packages on macOS — this commit can be reverted in its entirety:
the env-gate in `build-all.py` AND the `IFCOS_BUILD_PYTHON_WRAPPER=off`
in `build_osx.yml`. The bonsai macOS workflow will then build the
Python wrapper too.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.github/workflows/build_osx.yml

@@ -83,8 +83,14 @@ jobs:
           fi
           set -o pipefail
           export QT_DIR="$(brew --prefix qt)"
+          # IFCOS_BUILD_PYTHON_WRAPPER=off skips IfcOpenShell-Python on
+          # macOS until the plug-in refactor's CREATE_BUNDLE install rule
+          # actually drops ifcopenshell.document.rdb.dylib into
+          # site-packages/ifcopenshell/ (see the commit that added this
+          # gate for the full history + the rocksdb/macdeployqt write-up).
           CXXFLAGS="-O3" CFLAGS="-O3 ${DARWIN_C_SOURCE}" ADD_COMMIT_SHA=1 BUILD_CFG=Release \
             BUILD_BONSAIVIEWER=ON QT_DIR="${QT_DIR}" \
+            IFCOS_BUILD_PYTHON_WRAPPER=off \
             python3 ./nix/build-all.py -v --diskcleanup ${MAC_INTEL} \
             | tee build.log
 

nix/build-all.py

@@ -409,6 +409,14 @@ if not explicit_targets and not BUILD_BONSAIVIEWER:
     targets.difference_update({"BonsaiViewer", "qt6"})
 if BUILD_BONSAIVIEWER:
     targets.update(gather_dependencies("BonsaiViewer"))
+
+# Opt-out for the Python wrapper. Currently used by the bonsai CI workflow
+# on macOS, where the post-plug-in-refactor wrapper hard-links
+# ifcopenshell.document.rdb.dylib but the CREATE_BUNDLE install rule does
+# not actually drop the dylib next to the wrapper in site-packages — see
+# the commit message that introduced this gate.
+if os.environ.get("IFCOS_BUILD_PYTHON_WRAPPER", "on").lower() in {"0", "off", "false", "no"}:
+    targets.discard("IfcOpenShell-Python")
 if WASM:
     SKIP_TARGETS_FOR_WASM = {
         "rocksdb",