feat: Added Inventory and Item components

- Moved input tests into nested module
- Added inventory tests

src/inventory/item.rs

@@ -0,0 +1,35 @@
+use bevy::prelude::*;
+
+#[derive(Component, Clone)]
+pub struct Item {
+    pub size: UVec2,
+    pub position: Option<UVec2>,
+}
+
+impl Item {
+    pub fn new(size: UVec2) -> Self {
+        Self { size, position: None }
+    }
+
+    pub fn new_positioned(size: UVec2, position: UVec2) -> Self {
+        Self { size, position: Some(position) }
+    }
+
+    pub fn rect(&self) -> Option<URect> {
+        let Some(position) = self.position else {
+            return None;
+        };
+
+        Some(URect::from_corners(position, position + self.size))
+    }
+    
+    pub fn overlaps(&self, other_size: UVec2, other_position: UVec2) -> bool {
+        let Some(rect) = self.rect() else {
+            return false;
+        };
+
+        let other_rect = URect::from_corners(other_position, other_position + other_size);
+        
+        !rect.intersect(other_rect).is_empty()
+    }
+}