Pin Blender for CI asset processing

.gitea/workflows/ci.yml

@@ -63,7 +63,6 @@ jobs:
             libxkbcommon-dev \
             libxkbcommon-x11-0 \
             mesa-vulkan-drivers \
-            blender \
             mold \
             pkg-config
 
@@ -136,16 +135,45 @@ jobs:
             llvm-19 \
             mesa-vulkan-drivers \
             mold \
-            blender \
             pkg-config
           sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-19 100
           sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-19 100
           echo "/usr/lib/llvm-19/bin" >> "$GITHUB_PATH"
           rm -f "$HOME/.cache/cargo-xwin/clang-cl"
 
+      - name: Install pinned Blender
+        run: |
+          scripts/install-blender.sh "$RUNNER_TEMP/blender"
+          echo "BLENDER=$RUNNER_TEMP/blender/blender" >> "$GITHUB_ENV"
+
       - name: Preprocess assets
         run: cargo run --locked --bin process-assets --no-default-features --features debug_features -j 4
 
+      - name: Verify processed battlefield asset
+        run: |
+          python3 - <<'PY'
+          import json
+          import struct
+
+          path = "imported_assets/Default/stages/battlefield/bf2.blend"
+          with open(path, "rb") as asset:
+              header = asset.read(12)
+              if len(header) != 12:
+                  raise SystemExit(f"processed asset is truncated: {path}")
+              magic, version, length = struct.unpack("<4sII", header)
+              if magic != b"glTF" or version != 2 or length != asset.seek(0, 2):
+                  raise SystemExit(f"processed asset is not a valid GLB: {path}")
+              asset.seek(12)
+              json_length, chunk_type = struct.unpack("<II", asset.read(8))
+              if chunk_type != 0x4E4F534A:
+                  raise SystemExit(f"processed asset has no JSON chunk: {path}")
+              document = json.loads(asset.read(json_length))
+          meshes = document.get("meshes", [])
+          if not meshes:
+              raise SystemExit(f"processed asset contains no meshes: {path}")
+          print(f"{path}: {len(meshes)} meshes, {length} bytes")
+          PY
+
       - name: Build production binary
         run: cargo build --locked --profile production --no-default-features --features debug_features -j 4