build-all: make BonsaiViewer a normal target, built by default

Can be skipped using `--without-BonsaiViewer` as any other target, if
needed.

.github/workflows/build_osx.yml

@@ -104,7 +104,7 @@ jobs:
           # .dylib` failed to resolve at import time. ifcwrap now sets
           # INSTALL_RPATH to "@loader_path" on Apple.
           CXXFLAGS="-O3" CFLAGS="-O3 ${DARWIN_C_SOURCE}" ADD_COMMIT_SHA=1 BUILD_CFG=Release \
-            BUILD_BONSAIVIEWER=ON QT_DIR="${QT_DIR}" \
+            QT_DIR="${QT_DIR}" \
             uv run ./nix/build-all.py -v --diskcleanup --ifcopenshell-shared ${MAC_INTEL} \
             | tee build.log
 

.github/workflows/build_rocky.yml

@@ -75,7 +75,7 @@ jobs:
         shell: bash
         run: |
           set -o pipefail
-          CXXFLAGS="-O3" CFLAGS="-O3" ADD_COMMIT_SHA=1 BUILD_CFG=Release BUILD_BONSAIVIEWER=ON \
+          CXXFLAGS="-O3" CFLAGS="-O3" ADD_COMMIT_SHA=1 BUILD_CFG=Release \
             uv run --with aqtinstall ./nix/build-all.py \
             -v --diskcleanup --ifcopenshell-shared 2>&1 \
             | tee build.log

.github/workflows/build_rocky_arm.yml

@@ -87,7 +87,7 @@ jobs:
         shell: bash
         run: |
           set -o pipefail
-          CXXFLAGS="-O3" CFLAGS="-O3" ADD_COMMIT_SHA=1 BUILD_CFG=Release BUILD_BONSAIVIEWER=ON \
+          CXXFLAGS="-O3" CFLAGS="-O3" ADD_COMMIT_SHA=1 BUILD_CFG=Release \
             uv run --with aqtinstall ./nix/build-all.py \
             -v --diskcleanup --ifcopenshell-shared 2>&1 \
             | tee build.log