add engine builder node

[ryanontheinside]

Add EngineBuilder Node for YoloNasPose-Tensorrt

Description

This PR adds a new EngineBuilder node to the ComfyUI-YoloNasPose-Tensorrt extension, allowing users to easily build TensorRT engines from ONNX models directly in ComfyUI.

Changes

• Created new engine builder node

Features

• Model Selection: Choose from the supported ONNX models
• Custom Engine Names: Option to specify custom engine file names
• Custom ONNX Models: Support for using custom ONNX models
• Automatic Downloads: Auto download onnx from HF, and build engine
• User Feedback: Clear status messages for all operations

Usage

1. Add the "YoloNasPose Engine Builder" node to your workflow
2. Select the desired model size
3. (Optional) Configure custom engine name and FP16 settings
4. Run the workflow to build the TensorRT engine

Technical Details

• Models are downloaded to models/onnx/yolo-nas-pose/
• Engines are built in models/tensorrt/yolo-nas-pose/
• Supports both predefined and custom ONNX models
• Includes proper error handling and status reporting

Testing

• Tested with some models sizes in ComfyUI (method 1)
• Tested with some model sizes by running the script directly (method 2)