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

src/engine/legal.ts

@@ -252,7 +252,11 @@ function placementCandidates(s: GameState, player: PlayerIndex): GridCoord[] {
       // Q7 — a district hangs BELOW the Running Track; there is nothing above it.
       if (c.row > area.runningRow) continue;
       const k = `${c.row},${c.col}`;
-      if (area.grid.has(k) || seen.has(k)) continue;
+      if (seen.has(k)) continue;
+      // The Limits signs are candidates even though they are occupied: laying track there is how
+      // the Running Track grows, and the sign moves outward (§2.1). `check` still has the final say.
+      const occupied = area.grid.get(k);
+      if (occupied && !(occupied.geometry.kind === 'limits' && c.row === area.runningRow)) continue;
       seen.add(k);
       out.push(c);
     }