Restructure README for readability with progressive disclosure

Update README with diagnostic agent documentation

Rewrite README for clarity: add quick start, streamline structure

Rename model health to model internals across the full stack

Update minimum Node.js version to 20.19+ for Vite compatibility

Add Node.js 18+ installation to GPU setup script and clarify README

Add table of contents and fix README section hierarchy

Add web viewer documentation and screenshots to README

Improve visualization interpretability and add --image-map flag

Rearrange grid: interpretable overlays at bottom, raw maps at top

Update example grid asset with 7-row gradient attribution output

Add gradient-based attribution (saliency + GradCAM) for SmolVLA

Refresh README assets with threshold-corrected heatmaps

Add percentile thresholding and per-head baseline subtraction for SigLIP heatmaps

Sync README examples with defaults.yaml and add health report assets

Add interpretability roadmap to README

Add model health diagnostics and architecture documentation

Update README to reflect current visualization pipeline

Move supplementary docs into docs/ directory

Initial commit: SmolVLA attention visualizer