split joints and colliders out of rapier context

I'm not totally convinced yet, this leads to unfortunate API impacts to users, + bevy_mod_debugdump a bit difficult to parse, see jakobhellermann/bevy_mod_debugdump#50

bevy_rapier3d/examples/ray_casting3.rs

@@ -77,6 +77,7 @@ pub fn cast_ray(
     mut commands: Commands,
     windows: Query<&Window, With<PrimaryWindow>>,
     rapier_context: ReadDefaultRapierContext,
+    rapier_context_colliders: ReadDefaultRapierContextColliders,
     cameras: Query<(&Camera, &GlobalTransform)>,
 ) {
     let window = windows.single();
@@ -94,6 +95,7 @@ pub fn cast_ray(
 
         // Then cast the ray.
         let hit = rapier_context.cast_ray(
+            &rapier_context_colliders,
             ray.origin,
             ray.direction.into(),
             f32::MAX,

src/control/character_controller.rs

@@ -2,7 +2,7 @@ use crate::geometry::{Collider, CollisionGroups, ShapeCastHit};
 use crate::math::{Real, Rot, Vect};
 use bevy::prelude::*;
 
-use crate::plugin::RapierContext;
+use crate::plugin::{RapierContext, RapierContextColliders};
 pub use rapier::control::CharacterAutostep;
 pub use rapier::control::CharacterLength;
 use rapier::prelude::{ColliderSet, QueryFilterFlags};
@@ -26,7 +26,7 @@ pub struct CharacterCollision {
 
 impl CharacterCollision {
     pub(crate) fn from_raw(
-        ctxt: &RapierContext,
+        ctxt: &RapierContextColliders,
         c: &rapier::control::CharacterCollision,
     ) -> Option<Self> {
         Self::from_raw_with_set(&ctxt.colliders, c, true)
@@ -37,7 +37,7 @@ impl CharacterCollision {
         c: &rapier::control::CharacterCollision,
         details_always_computed: bool,
     ) -> Option<Self> {
-        RapierContext::collider_entity_with_set(colliders, c.handle).map(|entity| {
+        RapierContextColliders::collider_entity_with_set(colliders, c.handle).map(|entity| {
             CharacterCollision {
                 entity,
                 character_translation: c.character_pos.translation.vector.into(),