Thasia v0.4.1

Added

• Double-page spread splitter — manga with facing pages can now be split into individual pages with configurable LTR/RTL reading direction handling.
• Auto-crop whitespace transform — scan borders and surrounding whitespace can now be automatically cropped with configurable padding around the content.
• Bilateral filter for noise reduction — optional moire pattern and screentone reduction before scaling for improved output on heavily screened source material.
• Floyd-Steinberg dithering — 16-level grayscale quantization for e-ink output with ordered dithering.

Changed

• Tone clamping smoothing — binary near-white/near-black tone clamping replaced with smoothstep Hermite interpolation for smoother tonal transitions.
• Color saturation — replaced luma-based saturation with perceptually uniform Oklab chroma scaling for more accurate color balance.
• Image scaling — now uses Lanczos3 scaling in linear light to preserve thin-line brightness and detail.
• Gamma conversion optimization — replaced allocation-heavy gamma conversion with in-place LUT-based passes for improved memory efficiency.
• Pipeline module structure — internal pipeline and transform stages split into focused submodules (~300 lines/file) for better maintainability.