add FPS diagnostics

src/main.rs

@@ -5,6 +5,7 @@ mod world;
 mod settings;
 
 use bevy::window::{Window, WindowMode, PrimaryWindow, CursorGrabMode };
+use bevy::diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin};
 use bevy::prelude::*;
 
 fn main() {
@@ -24,6 +25,10 @@ fn main() {
         ))
         .add_plugins(DefaultPlugins.set(ImagePlugin::default_nearest()))
         .add_plugins(camera::CameraControllerPlugin)
+        .add_plugins((
+            FrameTimeDiagnosticsPlugin,
+            LogDiagnosticsPlugin::default(),
+        ))
         .run();
 }