feat(scene): keep map tokens with preview rotation

When previewRotationDeg changes, remap non-player, NPC and trap
markers (plus live session token overrides) so they stay on the art.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/main/players/scenePlayerTokensSessionStore.ts

@@ -5,6 +5,7 @@ import {
   type ScenePlayerTokensSessionEvent,
   type ScenePlayerTokensSessionState,
 } from '../../shared/types/appPlayers';
+import { rotateMapNormPointByCwSteps } from '../../shared/types/scenePreviewRotation';
 
 function emptyState(revision = 1): ScenePlayerTokensSessionState {
   return {
@@ -60,6 +61,27 @@ export class ScenePlayerTokensSessionStore {
     return this.state;
   }
 
+  /** Rotate live player tokens with the scene preview (CSS rotate steps). */
+  rotateMapCwSteps(steps: number): ScenePlayerTokensSessionState {
+    const n = ((steps % 4) + 4) % 4;
+    if (n === 0) return this.state;
+    const ids = Object.keys(this.state.byPlayerId);
+    if (ids.length === 0) return this.state;
+    const byPlayerId: ScenePlayerTokensSessionState['byPlayerId'] = {};
+    for (const id of ids) {
+      const prev = this.state.byPlayerId[id];
+      if (!prev) continue;
+      const p = rotateMapNormPointByCwSteps(prev.nx, prev.ny, n);
+      byPlayerId[id] = { ...prev, nx: p.nx, ny: p.ny };
+    }
+    this.state = {
+      ...this.state,
+      revision: this.state.revision + 1,
+      byPlayerId,
+    };
+    return this.state;
+  }
+
   dispatch(event: ScenePlayerTokensSessionEvent): ScenePlayerTokensSessionState {
     switch (event.kind) {
       case 'clear':