Add independent Rust engine, deterministic mod API and asset pipeline

build.rs

@@ -0,0 +1,9 @@
+fn main() {
+    println!("cargo:rerun-if-env-changed=HOME");
+    if let Ok(home) = std::env::var("HOME") {
+        let local = std::path::Path::new(&home).join(".local/lib");
+        if local.join("libSDL2.so").exists() {
+            println!("cargo:rustc-link-search=native={}", local.display());
+        }
+    }
+}