Move with collision reacts along the contact normal: it travels to the surface, stays flush and slides the rest of the move along it with Coulomb friction (the mean of both colliders, a tile counts as 0.5), a circle now rolls over an edge instead of catching on it, pushed dynamic bodies move off along the normal, Move gains the outputs hit, normal x and normal y, an object without its own collider moves freely, and editor run and play share the same path through Solids; contact point and normal come from our own f64 geometry (contactBetween), because Rapier's castShape lands 3e-6 px inside the wall in f32 (#150)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/runtime/physics/PhysicsSystem.ts

@@ -26,6 +26,7 @@ import {
   bodyOf,
   type CollisionPair,
   type CollisionSource,
+  type MoveResult,
   partsOf,
   shapeOf,
   Solids,
@@ -169,12 +170,7 @@ export class PhysicsSystem implements System, CollisionSource {
    * `Move` with "Collide with solids": the object stops at what is in the way and slides along it,
    * as in the editor run, and a dynamic body that stops it gets a push (#147).
    */
-  moveAndSlide(
-    world: World,
-    entity: Entity,
-    dx: number,
-    dy: number,
-  ): { blockedX: boolean; blockedY: boolean } {
+  moveAndSlide(world: World, entity: Entity, dx: number, dy: number): MoveResult {
     return this.solids.moveAndSlide(world, entity, dx, dy, (blocked) => this.push(world, entity, blocked));
   }
 
@@ -253,7 +249,7 @@ export class PhysicsSystem implements System, CollisionSource {
   }
 
   /**
-   * A mover that runs into a dynamic body pushes it along its travel, as one body meeting another
+   * A mover that runs into a dynamic body pushes it into the contact, as one body meeting another
    * without bounce: the wanted speed is the move spread over the frame, and a light mover barely
    * shifts a heavy crate. Both keep moving – the mover as the graph says, the crate as the engine does.
    */