added the server with a health check

added .env.example, also removed the old empty config file

crates/server/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "server"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+axum = { version = "0.8.9", features = ["tokio", "ws"] }
+tokio = { version = "1.52.3", features = ["full"] }

crates/server/src/main.rs

@@ -0,0 +1,28 @@
+use axum::{Router, routing::get};
+use tokio::net::TcpListener;
+
+#[tokio::main]
+async fn main() {
+    let app = Router::new().route("/health", get(health_check));
+
+    let address = {
+        let port = std::env::var("PORT")
+            .unwrap_or_else(|_| "8080".to_string())
+            .parse::<u16>()
+            .expect("PORT must be a valid u16");
+        let host = std::env::var("HOST").unwrap_or_else(|_| "127.0.0.1".to_string());
+        format!("{}:{}", host, port)
+    };
+
+    let listener = TcpListener::bind(&address)
+        .await
+        .expect("Failed to bind to address");
+
+    println!("Server running on http://{}", address);
+
+    axum::serve(listener, app).await.unwrap();
+}
+
+async fn health_check() -> &'static str {
+    "OK"
+}