added hello world demo

Cargo.toml

@@ -25,5 +25,9 @@ color-eyre = "0.6.2"
 name = "xr"
 path = "examples/xr.rs"
 
+[[example]]
+name = "demo"
+path = "examples/demo/src/main.rs"
+
 [profile.release]
 debug = true

examples/demo/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "demo"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

examples/demo/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello, world!");
+}