Persist watch rom setting

src/config.rs

@@ -143,6 +143,8 @@ pub struct SimConfig {
     #[serde(default)]
     pub low_battery: bool,
     #[serde(default)]
+    pub watch_rom: bool,
+    #[serde(default)]
     pub position: Option<Pos2>,
 }
 
@@ -157,6 +159,7 @@ impl SimConfig {
             dimensions: DisplayMode::Anaglyph.proportions() + Vec2::new(0.0, 22.0),
             audio_enabled: true,
             low_battery: false,
+            watch_rom: false,
             position: None,
         }
     }