feat(exporters): scaffold PngExporter

crates/exporters/src/lib.rs

@@ -1,8 +1,10 @@
+mod image_export;
 mod litematica;
 mod mcfunction;
 
 use lib::{BlockPalette, StructureExporter};
 
+pub use image_export::PngExporter;
 pub use litematica::LitematicaExporter;
 pub use mcfunction::McFunctionExporter;
 
@@ -11,12 +13,17 @@ type ExporterFactory = fn(&BlockPalette) -> Box<dyn StructureExporter>;
 const REGISTRY: &[(&str, ExporterFactory)] = &[
     ("mcfunction", |p| Box::new(McFunctionExporter::new(p))),
     ("litematica", |p| Box::new(LitematicaExporter::new(p))),
+    ("png", |p| Box::new(PngExporter::new(p, 16))),
 ];
 
 pub fn available_names() -> Vec<&'static str> {
     REGISTRY.iter().map(|(name, _)| *name).collect()
 }
 
+pub fn build_png(palette: &BlockPalette, cell_size: u32) -> Box<dyn StructureExporter> {
+    Box::new(PngExporter::new(palette, cell_size))
+}
+
 pub fn build(name: &str, palette: &BlockPalette) -> Option<Box<dyn StructureExporter>> {
     REGISTRY.iter()
         .find(|(n, _)| *n == name)