Fix test_body_motion() sometimes failing to extracting collision information

[madmiraal]

Currently, in Godot physics 2D and 3D, test_body_motion() sometimes fails to extract collision information, which results in the collision being ignored. This problem is aggravated when the collision margin is reduced. The most common reason for reducing collision margins is to overcome the problem that touching, but not overlapping objects are treated as colliding. This PR ensures:

1. Collision information is always correctly extracted regardless of the size of the collision margin
2. Touching, but not overlapping objects are not treated as colliding

Fixes #16414
Fixes #23140
Fixes #36432
Fixes #37798
Fixes #43346
Addresses comment

Although these issues all have the same source, fixing them required making multiple changes:

• Removing the dependence on a minimum contact depth
• Removing collision solver checks for a minimum penetration
• Preventing zero overlaps from being detected as collisions
• Ensuring that the 3D Godot physics static and distance collision algorithms treat zero pixel overlaps the same

To facilitate these changes this PR has refactored Godot 2D and 3D SpaceSW, the Godot GJK EPA API and the Godot 3D solve_distance() algorithm. I have kept all these changes in separate commits to facilitate review and potential future troubleshooting (the refactoring changes modified a lot of lines of code, but they should not change behaviour).

The refactoring of SpaceSW is comprehensive. To isolate the disparate issues, the code was standardised, which involved:

• Removing duplicated code, unnecessary loops and unnecessary checks
• Adding missing checks and generating appropriate errors
• Making all functions across 2D and 3D as similar as possible.
• Changing variable names so the code is easier to understand.

[madmiraal]

Rebased following merge of #42574.

[madmiraal]

Rebased following merge of #43923.

[madmiraal]

Rebased following merge of #45519.

[madmiraal]

Rebased following merge of #37547.

[madmiraal]

Rebased following merge of #45852.

[madmiraal]

Rebased following merge of #45854.

[Emalton]

Is this something that can be merged? It appears like it could fix this type of behavior?
https://i.imgur.com/fdlxuTg.gif

[YuriSizov]

A lot of the linked issues have been addressed in other PRs, and this hasn't been updated in a while. So I think this needs to be remade against the current master to only fix the remaining issues.

[Emalton]

@madmiraal Could you rebase your? Many of the issues you listed have been fixed already, but #23140 and #43346 are still not fixed so it would be great if your fixes could be upstreamed!