HDRLoader

Parses Radiance RGBE/HDR byte streams into CPU-friendly image data. Flat 32-bit_rgbe and scanline-RLE 32-bit_rle_rgbe payloads are decoded with their orientation metadata, converted to linear RGB samples, and packed as exposure-adjusted, tone-mapped sRGB RGBA bytes for DataTexture. Header and output-size limits keep parsing and allocation bounded for Canvas2D use.