Add window surface resizing function

src/gfx/context.rs

@@ -68,4 +68,13 @@ impl Context {
             queue,
         }
     }
+
+    pub fn resize(&mut self, new_size: PhysicalSize<u32>) {
+        if new_size.width > 0 && new_size.height > 0 {
+            self.size = new_size;
+            self.surface_config.width = new_size.width;
+            self.surface_config.height = new_size.height;
+            self.surface.configure(&self.device, &self.surface_config);
+        }
+    }
 }