Initial commit: Terrafier v0.1.0

- Core world model (World, Dimension, Tile, Terrain, Platform)
- NBT reader/writer with full tag support
- Anvil region (.mca) format reader with chunk parsing
- Block palette compression and export
- Biome database with Minecraft 1.21 biomes
- CLI commands: new, import, export, info, render
- GUI application with egui (viewport, tools, undo/redo)
- Noise-based heightmap generation and editing operations

License: GPL-3.0-or-later

gui/src/main.rs

@@ -0,0 +1,15 @@
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    env_logger::init();
+    let native_options = eframe::NativeOptions::default();
+    eframe::run_native(
+        "Terrafier",
+        native_options,
+        Box::new(|_cc| Ok(Box::new(app::TerrafierApp::new()))),
+    )?;
+    Ok(())
+}
+
+mod app;
+mod dialogs;
+mod tools;
+mod view;