This commit fixes the behavior of the tooltip
enabled by the zoom option which displays
the full image when the field is hovered.
Before the commit, the preview_image option was
not used by the field and the full value was used
for both the field image and the tooltip.
A test has been introduced to check that the
field uses the right images sources when both
attributes are present.
closesodoo/odoo#95208
Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>