Add stocks UI (#52)

Reviewed-on: #52
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

src/ui/stock_icon.rs

@@ -0,0 +1,17 @@
+use bevy::prelude::*;
+
+#[derive(SceneComponent, Clone, FromTemplate)]
+pub struct BattleUIStockIcon;
+
+impl BattleUIStockIcon {
+    pub fn scene() -> impl Scene {
+        bsn! {
+            Node {
+                width: px(32),
+                height: px(32),
+                border_radius: BorderRadius::MAX,
+            }
+            BackgroundColor({bevy::color::palettes::css::RED})
+        }
+    }
+}