Inverted height and width in create_anchors

[giovanni-violo]

The create_anchors() function assumes image_size=(H, W) while the rest of the code defines it as (W, H). This axis swap leaves part of the image without anchors, causing missing positives and NaN losses. It went unnoticed with the original dataset, where the satellite was always near the center, but appears with datasets covering a wider pose range.