⚡ Optimize MicrotubuleTorus rendering with InstancedMesh

[jason420247]

💡 What:
Optimized the MicrotubuleTorus component by replacing individual mesh components with a single THREE.InstancedMesh. The implementation uses a reusable THREE.Object3D for efficient matrix updates within the useFrame loop and properly manages the instanceMatrix.needsUpdate flag.

🎯 Why:
Rendering thousands of individual meshes (360 + 720 = 1080 in the default scene) is extremely expensive for the GPU due to excessive draw calls. Using InstancedMesh batches these into a single draw call per torus, significantly improving rendering performance and CPU efficiency.

📊 Measured Improvement:

• Draw Calls: Reduced from 1080 to 2 for the two MicrotubuleTorus instances.
• CPU Overhead: Minimizing scene graph complexity reduces the overhead of the R3F loop and Three.js frustum culling checks.
• Safety: Added key={count} to handle dynamic instance count changes and frustumCulled={false} to prevent flickering during complex animations.

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PR created automatically by Jules for task 15101849277777753923 started by @jason420247

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