Minecarts on sloped rails have two collision boxes

Problem Summary：

A minecart on a sloped rail has two collision boxes at the same time. This is not expected behavior and causes incorrect collision results.

This issue can be demonstrated by whether a minecart can enter a rail. The actual affected situations are broader than this example.

Additional information:

The condition for a minecart entering a rail is that the minecart center enters the rail block and the block above the rail. This is normal behavior and explains the situations where a minecart can move onto a rail.

Reproduce the problem steps

Version 1.20

The minecart collision box moves horizontally one block above the sloped rail.

Moving horizontally into the sloped rail

Because the collision box is one block above the sloped rail, the minecarts do not collide with each other, so the minecart directly enters the sloped rail.

Moving from above to below

The upper minecart is standing on the minecart located on the sloped rail, so the minecart cannot enter the sloped rail.

Version 1.21

The minecart collision box moves horizontally in the same block as the sloped rail.

Moving horizontally into the sloped rail

Because the collision box is in the same block as the sloped rail, the minecarts collide with each other.

Moving from above to below

Before collision occurs, the minecart already enters the upper rail area, so it directly enters the sloped rail.

Additional information after 26.20.20

After 26.20.20, the collision box was changed to have directionality. This information is provided to avoid inconsistent reproduction results. This issue is MCPE-238885.

Version 26.40.20

The minecart has two collision boxes:

One collision box moves horizontally one block above the sloped rail.

Another collision box moves horizontally in the same block as the sloped rail.

Moving horizontally into the sloped rail

Because one collision box is in the same block as the sloped rail, the minecarts collide with each other.

Moving from above to below

The upper minecart is standing on the minecart located on the sloped rail, so the minecart cannot enter the sloped rail.

Expected Result

The minecart should only have one collision box when moving on a sloped rail.

Version 1.20 and version 1.21 both have reasonable collision behaviors, but having two collision boxes at the same time creates incorrect behavior. Considering keeping the fix of MCPE-216837, the version 1.20 collision behavior can be used as the standard.