refactor: move trainer/models/utils/config to tools/

tools/utils.py

@@ -0,0 +1,25 @@
+# sites/ai_mouse/ai_mouse/_utils.py
+"""Shared utility functions used by both _generator.py and _trainer.py."""
+from __future__ import annotations
+
+import numpy as np
+
+
+def resample_arc(xy: np.ndarray, n_points: int) -> np.ndarray:
+    """Resample a 2-D polyline to exactly n_points via arc-length interpolation.
+
+    Args:
+        xy: (M, 2) array of (x, y) coordinates.
+        n_points: desired number of output points.
+
+    Returns:
+        (n_points, 2) array uniformly spaced along cumulative arc length.
+    """
+    arc = np.concatenate(
+        [[0], np.cumsum(np.linalg.norm(np.diff(xy, axis=0), axis=1))]
+    )
+    s_new = np.linspace(0, arc[-1], n_points)
+    return np.stack(
+        [np.interp(s_new, arc, xy[:, 0]), np.interp(s_new, arc, xy[:, 1])],
+        axis=1,
+    )