chore: rename executor -> evaluator and integrate into app

crates/app/src/main.rs

@@ -1,3 +1,5 @@
+use std::fs;
+
 use config::Config;
 use welcome_msg::print_startup_msg;
 
@@ -14,4 +16,14 @@ fn main() {
     if cfg.startup_msg {
         print_startup_msg();
     }
+
+    let source =
+        fs::read_to_string(cfg.source).expect("can't find source file lol handle me better please");
+
+    let ir =
+        ir::from_ron(&source).expect("aww failed to parse source to graph ir handle me better");
+
+    let mut machine = cfg.evaluator.pick();
+    machine.feed(ir);
+    machine.eval_full();
 }