Physics collision filtering (reopen)

[Wackytoaster]

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Summary

Please refer to #68 for more info/discussion
Some further info on this: https://www.iforce2d.net/b2dtut/collision-filtering
Box2D docs: https://box2d.org/documentation/group__shape.html#structb2_filter

Long story short, please add collision filtering to the physics plugin. The relevant features in box2D are categoryBits, maskBits and groupIndex

Possible workarounds or alternatives

There are plenty of things that are either extremely tricky if not impossible to work around without this feature. (e.g. jumpthrough platforms, see old feature request)
Or simply platforms that enemies can stand on but the player can't.

Proposed solution

Expose the box2D feature of categoryBits, maskBits and groupIndex

1. In the object properties
   

2. At runtime (set and get/expressions)
   

Why is this idea important?

Many times when I'm using the physics plugin I end up running into a wall with this exact issue. I need A to collide with B, and B with C, but not A with C. It's practically impossible to work around.

Additional remarks

Colludiums plugin is finally starting to die properly (somewhere between r420-r426) and throwing errors/freezing stuff. RIP, because it's not gonna get updated (so with SDKv2 it was dead either way) It was a goated plugin because it had this feature (among others)

Please make 2025 the big physics plugin update (there's other additional feature suggestions for physics out there too)