feat: add blender_export_primitives.py for exporting primitive models in GLTF format

tools/blender_export_primitives.py

@@ -0,0 +1,48 @@
+import bpy
+import os
+
+# Clear existing objects
+bpy.ops.object.select_all(action='SELECT')
+bpy.ops.object.delete()
+
+# Output directory
+output_dir = os.path.expanduser("~/.cache/starworld/primitives")
+os.makedirs(output_dir, exist_ok=True)
+
+# Create and export UV Sphere
+bpy.ops.mesh.primitive_uv_sphere_add(segments=32, ring_count=16, radius=0.5, location=(0, 0, 0))
+sphere = bpy.context.active_object
+sphere.name = "Sphere"
+bpy.ops.export_scene.gltf(
+    filepath=os.path.join(output_dir, "sphere.glb"),
+    export_format='GLB',
+    use_selection=True
+)
+print(f"Exported sphere.glb to {output_dir}")
+
+# Delete sphere and create cube
+bpy.ops.object.delete()
+bpy.ops.mesh.primitive_cube_add(size=1.0, location=(0, 0, 0))
+cube = bpy.context.active_object
+cube.name = "Cube"
+bpy.ops.export_scene.gltf(
+    filepath=os.path.join(output_dir, "cube.glb"),
+    export_format='GLB',
+    use_selection=True
+)
+print(f"Exported cube.glb to {output_dir}")
+
+# Delete cube and create ico sphere for the "model" placeholder
+bpy.ops.object.delete()
+bpy.ops.mesh.primitive_ico_sphere_add(subdivisions=2, radius=0.5, location=(0, 0, 0))
+ico = bpy.context.active_object
+ico.name = "IcoSphere"
+bpy.ops.export_scene.gltf(
+    filepath=os.path.join(output_dir, "model.glb"),
+    export_format='GLB',
+    use_selection=True
+)
+print(f"Exported model.glb to {output_dir}")
+
+print("\n✓ All primitive models exported successfully!")
+print(f"Location: {output_dir}")