This backports the improved RayCast debug drawing functionality
from the `master` branch.
`ArrayMesh.clear_surfaces()` was also backported from the `master`
branch and exposed because the new debug drawing code requires it.
We already removed it from the online docs with #35132.
Currently it can only be "Built-In Types" (Variant types) or "Core"
(everything else), which is of limited use.
We might also want to consider dropping it from `ClassDB` altogether
in Godot 4.0.
- Document a few more properties and methods
- Add more information to many classes
- Fix lots of typos and gramar mistakes
- Use [code] tags for parameters consistently
- Use [b] and [i] tags consistently
- Put "Warning:" and "Note:" on their own line to be more visible,
and make them always bold
- Tweak formatting in code examples to be more readable
- Use double quotes consistently
- Add more links to third-party technologies
In many of the XML files it had been noted that when the documentation
refers to a return value, both "Return" and "Returns" are used. This
has now been fixed to only say "Returns".
Fixes#28867
The point is that `RayCast`s are checked against objects' `collision_layer`(s), but they themselves are considered no to _belong_ to any layer. Therefore, the correct name for their property is `collision_mask`, rather than `collision_layer`.
Only renaming is needed since the behavior was already the right one, only that it wasn't matching what users would expect from the name and description of the property.
Fixes#7589, where it's also discussed.
