Cargo skeleton

Boilerplate from running `cargo init --lib`, and `cargo build`.
Also added Cargo.lock to .gitignore (this is a library crate).

.gitignore

@@ -0,0 +1,2 @@
+/target
+Cargo.lock

Cargo.toml

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

src/lib.rs

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