Add Pneumonia Detection AI model under medical imaging (#252)

[2004ARYAN]

📌 Summary

This PR adds support for Pneumonia Detection AI using chest X-ray images as part of issue #252 — “Medical Imaging AI”.

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✅ What's Included

• pneumonia_model.py — Torch-based classifier with ResNet18
• pneumonia_model.pth — Trained weights file
• config.yaml — Model configuration file for IGEL integration
• infer.py — Example script to run inference on chest X-rays
• pneumonia_notebook.ipynb — Kaggle notebook used for training & reference

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📂 Folder Structure

igel/
├── medical/
│ └── models/
│ ├── pneumonia_model.py
│ ├── pneumonia_model.pth
│ └── config.yaml
examples/
└── pneumonia_detection/
├── infer.py
igel/
└── examples/
└── pneumonia_detection/
└── pneumonia_notebook.ipynb

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🧪 Test Instructions

Run the model with:

python examples/pneumonia_detection/infer.py path_to_chest_xray.jpg

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[2004ARYAN]

Hi @nidhaloff 👋

This PR adds pneumonia detection support using a pretrained ResNet model trained on chest X-rays (see #252). It includes:

• Model weights (.pth)
• Inference script
• Config file
• Example usage
• Kaggle notebook for full training reference

Let me know if you’d like ONNX export or evaluation script as a follow-up. Excited to contribute to medical AI with IGEL!

Thanks 🙌
– Aryan