Add initial rust configs

Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "backend"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+actix = "0.13"
+tokio = { version = "1.44", features = ["full"] }

src/main.rs

@@ -0,0 +1,5 @@
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    println!("Hello, world!");
+    Ok(())
+}