WASM plugins, scripting, i18n, GUI pan/zoom, cargo-dist CI/CD

- WASM plugin host (wasmtime 46, 17 host fns) + example noisemap plugin
- Rhai scripting engine (12 API fns, `terrafier run` cmd)
- i18n: en/ru translations, auto-detect, t! macro
- GUI: pan (click-drag) + zoom (scroll wheel) with viewport transform
- cargo-dist 0.31: MSI/pkg/shell installers, both binaries
- CI: .github/workflows/ci.yml + release.yml
- Security: wasmtime 30→46, bincode 1.3→2.0, quick-xml CVE docs
- Code review: SAFETY comments, unwrap→match cleanup
- Fixes: clippy approx_constant, needless_borrows, rustfmt

crates/scripting/tests/integration_test.rs

@@ -0,0 +1,56 @@
+use std::path::Path;
+
+use terrafier_core::World;
+use terrafier_scripting::ScriptEngine;
+
+#[test]
+fn test_new_world() {
+    let mut engine = ScriptEngine::new();
+    let result = engine
+        .run(
+            r#"
+        let world = new_world("test_world", 12345);
+        let i = info(world);
+        i.contains("test_world") && i.contains("12345")
+    "#,
+        )
+        .unwrap();
+    assert!(result.as_bool().unwrap());
+}
+
+#[test]
+fn test_generate_flat_heightmap() {
+    let mut engine = ScriptEngine::new();
+    let _ = engine
+        .run(
+            r#"
+        let world = new_world("flat_world", 42);
+        generate_heightmap_flat(world, 64, "overworld");
+        save_world(world, "/tmp/test_flat.tfw");
+    "#,
+        )
+        .unwrap();
+    let loaded: World = terrafier_core::io::load_binary(Path::new("/tmp/test_flat.tfw")).unwrap();
+    if let Some(dim) = loaded.dimensions.first() {
+        for (_, tile) in &dim.tiles {
+            for z in 0..128 {
+                for x in 0..128 {
+                    assert_eq!(tile.get_height(x, z), 64);
+                }
+            }
+        }
+    }
+    let _ = std::fs::remove_file("/tmp/test_flat.tfw");
+}
+
+#[test]
+fn test_script_error_reporting() {
+    let mut engine = ScriptEngine::new();
+    let result = engine.run(
+        r#"
+        let world = new_world("bad", 1);
+        generate_heightmap_flat(world, 64, "nonexistent");
+    "#,
+    );
+    assert!(result.is_err());
+}