feat: add function to get res from image number

src/aarecommon/math/find_xtal.py

@@ -1,6 +1,7 @@
 from collections.abc import Callable
 
 import numpy as np
+from jfjoch_client.models.scan_result_images_inner import ScanResultImagesInner
 from scipy import ndimage
 
 from aarecommon.config.logger import setup_logger
@@ -269,6 +270,16 @@ def get_best_res(result_list: list):
     return best_res.res
 
 
+def get_res_of_image_number(
+    result_list: list[ScanResultImagesInner], image_index: int | None
+) -> float | None:
+    if image_index is None or image_index >= len(result_list):
+        return None
+    image = result_list[image_index]
+    logger.info(f"Resolution estimage for selected gridscan image (# {image_index}): {image.res}")
+    return image.res
+
+
 def com_nan_check(com):
     return not (np.isnan(com.n_x) or np.isnan(com.n_y))