feat(simulator): add image saving utilities for verification

mini-nav/utils/image.py

@@ -0,0 +1,21 @@
+"""Image conversion utilities."""
+
+from __future__ import annotations
+
+import numpy as np
+from PIL import Image
+
+
+def numpy_to_pil(rgb: np.ndarray) -> Image.Image:
+    """Convert an RGB numpy array to a PIL Image.
+
+    Handles arrays with 4 channels (RGBA) by dropping the alpha channel.
+
+    Args:
+        rgb: Numpy array of shape (H, W, C) with dtype uint8 or compatible.
+
+    Returns:
+        PIL Image in RGB mode.
+    """
+    rgb3 = rgb[..., :3] if rgb.shape[-1] > 3 else rgb
+    return Image.fromarray(rgb3.astype(np.uint8))