Add Litematica exporter and integrate serde for serialization

- 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.

crates/lib/Cargo.toml

@@ -6,5 +6,6 @@ edition = "2024"
 [dependencies]
 ab_glyph = "0.2.32"
 anyhow = { workspace = true }
+serde = { workspace = true }
 thiserror = { workspace = true }
 tracing = { workspace = true }