various fixes. added version#s and added a playable browser build of the solitaire game (including deploy to filebrowser script)

src/engine/track.ts

@@ -330,7 +330,16 @@ export function allReachable(
  * stubs above and below so this is satisfiable from the opening Stage.
  */
 export function canPlaceAt(area: OfficeArea, coord: GridCoord, card: TrackCard): boolean {
-  if (cardAt(area, coord)) return false;
+  const existing = cardAt(area, coord);
+  // A Limits sign on the Running Track is the GROWTH POINT, not an obstacle. Extending means laying
+  // the card where the sign stands and moving the sign outward (§2.1, Gap 4a) — the physical act at
+  // the table. Treating the sign as occupied forced players to build PAST it, stranding the sign
+  // mid-track with everything beyond it nominally outside their own Limits.
+  const isMovableSign =
+    existing?.geometry.kind === 'limits' &&
+    coord.row === area.runningRow &&
+    existing.standing.length === 0;
+  if (existing && !isMovableSign) return false;
 
   const ports: Port[] = ['n', 's', 'e', 'w'];
   for (const p of ports) {