amg.build_point_grid function

Thanks for your great work !
when I read and understand the source code,
copilot gives another implemention of function "build_point_grid", which looks more concise and direct, maybe you could have a try
```
def build_point_grid2(n_per_side: int) -> np.ndarray:
"""Generates a 2D grid of points evenly spaced in [0,1]x[0,1]."""
offset = 1 / (2 * n_per_side)
points = np.mgrid[0:n_per_side, 0:n_per_side].transpose(2, 1, 0).reshape(-1, 2) / n_per_side + offset
return points

def build_point_grid(n_per_side: int) -> np.ndarray:
"""Generates a 2D grid of points evenly spaced in [0,1]x[0,1]."""
offset = 1 / (2 * n_per_side)
points_one_side = np.linspace(offset, 1 - offset, n_per_side)
points_x = np.tile(points_one_side[None, :], (n_per_side, 1))
points_y = np.tile(points_one_side[:, None], (1, n_per_side))
points = np.stack([points_x, points_y], axis=-1).reshape(-1, 2)

assert np.all(points == build_point_grid2(n_per_side))
return points
```

Start by locating the amg.build_point_grid entry point and compare its output with the proposed build_point_grid2 implementation. Done means the function remains behaviorally equivalent for its supported inputs and the relevant project checks pass.

Written by the indexing model from the issue text.