feat: init with rust lib and bin crate

templates/default/rust/app/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "app"
+edition = "2021"
+version.workspace = true
+
+[dependencies]
+lib = { path = "../lib" }
+
+anyhow = { workspace = true }
+log = { workspace = true }
+env_logger = { workspace = true }

templates/default/rust/app/src/main.rs

@@ -0,0 +1,6 @@
+fn main() {
+    let (a, b) = (1, 1);
+    let r = lib::add(a, b);
+
+    println!("{a} + {b} = {r}");
+}

templates/default/rust/lib/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "lib"
+edition = "2021"
+version.workspace = true
+
+[dependencies]
+anyhow = { workspace = true }
+log = { workspace = true }

templates/default/rust/lib/src/lib.rs

@@ -0,0 +1,14 @@
+pub fn add(left: u64, right: u64) -> u64 {
+    left + right
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let result = add(2, 2);
+        assert_eq!(result, 4);
+    }
+}