Add Bonsai tests to pull requests

Bonsai tests currently only run after merge (ci-bonsai-daily on
push to v0.9.0), so pull requests that touch src/bonsai are not
tested until it is too late. Add a pull_request-triggered workflow
that installs a working Bonsai/ifcopenshell from the public unstable
repo and runs the Bonsai tool test suite against the PR source.

Kept non-required initially because the suite has pre-existing
failures unrelated to this change.

Generated with the assistance of an AI coding tool.

.github/workflows/ci-bonsai-pr.yml

@@ -0,0 +1,58 @@
+# This file was generated with the assistance of an AI coding tool.
+name: ci-bonsai-pr
+
+on:
+  pull_request:
+    paths:
+      - 'src/bonsai/**'
+      - '.github/workflows/ci-bonsai-pr.yml'
+  workflow_dispatch:
+
+jobs:
+  bonsai-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout IfcOpenShell
+        uses: actions/checkout@v7
+
+      # The unstable repo provides a working Bonsai/ifcopenshell install; the
+      # tests themselves run against the source tree of this pull request.
+      - name: Checkout Bonsai unstable repo
+        uses: actions/checkout@v7
+        with:
+          repository: IfcOpenShell/bonsai_unstable_repo
+          path: bonsai_unstable_repo
+
+      - name: Download Blender
+        run: |
+          wget -q -O blender.tar.xz https://download.blender.org/release/Blender5.2/blender-5.2.0-linux-x64.tar.xz
+          tar -xf blender.tar.xz
+
+      - name: Install Bonsai
+        run: |
+          set -x -e
+          BLENDER_PATH=$(find blender-*/ -maxdepth 0 -exec readlink -f {} \;)
+          export PATH="$PATH:$BLENDER_PATH"
+          blender --version
+
+          cd bonsai_unstable_repo
+          pip install -r requirements.txt
+          python setup_extensions_repo.py --last-tag
+          cd ..
+          bonsai_zip="$(pwd)/$(ls bonsai_unstable_repo/bonsai_py313*-linux-x64.zip)"
+
+          blender --command extension install-file -r user_default -e $bonsai_zip
+          blender --command extension list
+
+      - name: Run Bonsai tests
+        run: |
+          set -x -e
+          BLENDER_PATH=$(find blender-*/ -maxdepth 0 -exec readlink -f {} \;)
+          export PATH="$PATH:$BLENDER_PATH"
+          blender --version
+
+          cd src/bonsai
+          pip install -r requirements-dev.txt
+          blender --background --python-exit-code 1 --python scripts/setup_pytest.py
+          blender --python-exit-code 1 --python-expr "import bonsai; print(bonsai.bbim_semver); import ifcopenshell; print(ifcopenshell.version)" --background
+          make test-tool