⚡ Optimize MicrotubuleTorus rendering with InstancedMesh

[jason420247]

💡 What: Replaced individual mesh rendering for each unit in the MicrotubuleTorus component with a single THREE.InstancedMesh.

🎯 Why: The previous implementation rendered hundreds of individual meshes (360 and 720 units respectively for the two toruses), resulting in over 1000 draw calls. This caused significant performance overhead in the rendering loop.

📊 Measured Improvement: Theoretically reduced draw calls for the microtubule structures from 1080 to 2. The use of InstancedMesh allows the GPU to render all instances in a single call per torus, while the use of a reusable THREE.Object3D for matrix calculations in useFrame minimizes memory allocation and garbage collection pressure.

---

PR created automatically by Jules for task 5598972451569882170 started by @jason420247

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.