Trigger colliders and Move and slide against solid colliders

- Collider property isTrigger (no blocking, still reports enter/stay/exit)
- Node 'Move and slide' with blocked x/y outputs, axis-wise resolution
- axisSeparation/axisCorrection geometry for box/box, circle/circle, box/circle
- Amber outline for trigger colliders in the viewport
- Demo mover uses Move and slide; E2E step 15b, 7 new unit tests

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/core/graph/NodeRegistry.ts

@@ -56,6 +56,11 @@ export interface NodeContext {
    * stands for itself; any other entity stands for its direct collider children.
    */
   isTouching(a: EntityHandle, b: EntityHandle): boolean;
+  /**
+   * Moves `target` by (dx, dy) in local units, stopping its solid colliders at other solid
+   * colliders axis by axis (x first, then y) so it slides along walls. Reports which axes hit.
+   */
+  moveAndSlide(target: EntityHandle, dx: number, dy: number): { blockedX: boolean; blockedY: boolean };
   log(message: string): void;
   destroy(target: EntityHandle): void;
   stop(): void;

src/core/graph/nodes.ts

@@ -307,6 +307,25 @@ registerNode({
     return { next: 'exec' };
   },
 });
+registerNode({
+  type: 'MoveAndSlide',
+  label: 'Move and slide',
+  category: 'action',
+  description: 'Like Move, but solid colliders of the object stop at other solid colliders and slide along them. Outputs which axes were blocked.',
+  inputs: [exec(), obj('object'), num('dx'), num('dy'), { ...num('scale'), default: 1 }, { ...num('dt'), default: 1 }],
+  outputs: [exec(), bool('blockedX', 'blocked x'), bool('blockedY', 'blocked y')],
+  params: [],
+  run: (ctx, i) => {
+    const target = asEntity(i.object);
+    let blockedX = false;
+    let blockedY = false;
+    if (target) {
+      const factor = asNumber(i.scale) * asNumber(i.dt);
+      ({ blockedX, blockedY } = ctx.moveAndSlide(target, asNumber(i.dx) * factor, asNumber(i.dy) * factor));
+    }
+    return { next: 'exec', outputs: { blockedX, blockedY } };
+  },
+});
 registerNode({
   type: 'SetPosition',
   label: 'Set position',