v2.5.21: Merge pull request #407 from AInVFX/main

• 🛠️ Fix: GGUF dequantization error on MPS - Resolved shape mismatch error introduced in 2.5.20 by skipping GGUF quantized buffers in precision conversion - these must remain in packed format for on-the-fly dequantization during inference
• 🍎 MPS: Eliminate CPU sync overhead - Skip unnecessary CPU tensor offload on Apple Silicon unified memory architecture, preventing sync stalls that caused slowdowns. Input images and output video now stay on MPS device throughout the pipeline
• ⚡ MPS: Preload text embeddings - Load text embeddings before Phase 1 encoding to avoid sync stall at Phase 2 start, improving timing accuracy and throughput
• 🧹 MPS: Optimized model cleanup - Skip redundant CPU movement before model deletion on unified memory