Added sanity check baseline made by claude.

Also changed the location to a panel in VIEW_3D instead of menu.

core/mesh.py

@@ -0,0 +1,32 @@
+"""Fast mesh data access with numpy."""
+
+import numpy as np
+
+
+def polygon_arrays(mesh):
+    """Return (loop_start, loop_total, loop_vertex_index) as int arrays."""
+    n_polys = len(mesh.polygons)
+    starts = np.empty(n_polys, dtype=np.int32)
+    totals = np.empty(n_polys, dtype=np.int32)
+    mesh.polygons.foreach_get("loop_start", starts)
+    mesh.polygons.foreach_get("loop_total", totals)
+    loop_verts = np.empty(len(mesh.loops), dtype=np.int32)
+    mesh.loops.foreach_get("vertex_index", loop_verts)
+    return starts, totals, loop_verts
+
+
+def loop_polygon_index(totals):
+    """Polygon index of every loop."""
+    return np.repeat(np.arange(len(totals), dtype=np.int32), totals)
+
+
+def vertex_coords(mesh):
+    co = np.empty(len(mesh.vertices) * 3, dtype=np.float64)
+    mesh.vertices.foreach_get("co", co)
+    return co.reshape(-1, 3)
+
+
+def polygon_normals(mesh):
+    normals = np.empty(len(mesh.polygons) * 3, dtype=np.float64)
+    mesh.polygon_normals.foreach_get("vector", normals)
+    return normals.reshape(-1, 3)