- Added PngExporter struct to generate PNG images from voxel grids.
- Implemented image dimensions calculation, drawing primitives, and legend rendering.
- Integrated PNG export functionality into the CLI with a new --cell-size flag.
- Removed outdated design spec and implementation plan documents.
- Introduced Litematica exporter with necessary data structures for Minecraft text generation.
- Added serde dependency for serialization support in multiple crates.
- Updated Cargo.toml files to include new dependencies and features.
- Created palette module for block palette management.