Illusion walls shimmer until YOU test them (rules rev 29)

Per the owner's design — and truer to a real table, where the cast is
public: every illusion wall's location is open knowledge, rendered as a
shimmering wall to any player whose eyes have not yet ruled on it.
Testing is an explicit act: tap the shimmer (or bump into it) and a
modal explains the 50/50 and offers 'Roll to test your eyes' — the new
testIllusion command rolls once, then the wall either hardens or
dissolves for you alone. Nobody's verdict is moved by watching someone
else stroll through (the Q3WZ mystery: an automaton walking through
its own round-1 fake). Untested walls block movement and sight without
consuming RNG; the pre-29 lazy belief roll is preserved for stored
games. Automatons doubt free shimmers on their best crossing before
spending any card on that wall.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0138A8CjeQRpvzKxuMfz1Bqc

packages/engine/src/automaton.ts

@@ -1308,6 +1308,21 @@ export function automatonCommand(
       pathToward(view, self.position, objectives, { avoidNearEnemies: style === "worrier" && !thief, canUnlock }) ??
       pathToward(view, self.position, objectives, { canUnlock }) ??
       pathToward(view, self.position, enemyCells, { canUnlock });
+    // A shimmering illusion on the best crossing costs nothing to doubt:
+    // roll the free test before spending any card on that wall (rev 29).
+    if (view.deckRev >= 29) {
+      const crossing = bestWallCrossing(view, self, objectives, canUnlock);
+      if (crossing && crossing.total < (path?.distance ?? Infinity)) {
+        const k = edgeKey(crossing.cell, crossing.side);
+        if (view.illusionEdges[k] === "untested") {
+          const sighted = sightedCellsFor(view);
+          const flanks = [crossing.cell, neighbor(crossing.cell, crossing.side)];
+          if (flanks.some((c) => cellKey(c) === cellKey(self.position) || sighted.has(cellKey(c)))) {
+            return { type: "testIllusion", cell: crossing.cell, side: crossing.side };
+          }
+        }
+      }
+    }
     // A wall between here and the gold may be cheaper to remove than to walk
     // around — and sometimes it is the only way through.
     const dw = inHand(view, "destroy-wall");