Add aspirinV2: fixed-cell 15-puzzle

Cells never move; each NumericSelectLabel shows the number it holds
on white and the empty cell takes the board colour via a linked
backgroundColor. Adds the V2 generator, build step (with a direct-Java
sedonac fallback), offline verifier mode (--v2) and viewer support.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

verify_logic.py

@@ -345,6 +345,128 @@ def main():
     print("re-shuffle OK")
 
 
+def astar(s0):
+    """Weighted A* on a 16-tuple (0 = blank); returns the list of cell indices to press."""
+    import heapq
+    goal = tuple(list(range(1, 16)) + [0])
+
+    def h(s):
+        return sum(abs(i // 4 - (v - 1) // 4) + abs(i % 4 - (v - 1) % 4)
+                   for i, v in enumerate(s) if v)
+
+    pq = [(h(s0), 0, s0, [])]
+    seen = {s0: 0}
+    while pq:
+        _, gc, s, p = heapq.heappop(pq)
+        if s == goal:
+            return p
+        z = s.index(0)
+        for dz in (-1, 1, -4, 4):
+            n = z + dz
+            if n < 0 or n > 15 or (dz in (-1, 1) and n // 4 != z // 4):
+                continue
+            l = list(s)
+            l[z], l[n] = l[n], l[z]
+            ns = tuple(l)
+            if seen.get(ns, 1e9) > gc + 1:
+                seen[ns] = gc + 1
+                heapq.heappush(pq, (gc + 1 + 1.5 * h(ns), gc + 1, ns, p + [n]))
+        if len(seen) > 2_000_000:
+            return None
+
+
+def main_v2():
+    """aspirinV2.sax: fixed cells, numbers shown via each cell's `in`, empty cell recoloured."""
+    tops, paths = load("aspirinV2.sax")
+    for c in paths.values():
+        c.start()
+    now = 0
+    goal = tuple(list(range(1, 16)) + [0])
+    cell = [paths[f"/ox/Game/Cell{i:02d}"] for i in range(1, 17)]
+
+    def step(n=1):
+        nonlocal now
+        for _ in range(n):
+            now += SCAN_MS + random.randint(-3, 3)
+            run_scan(tops, now)
+
+    def state():
+        return tuple(int(c.g("in")) for c in cell)
+
+    def check():
+        s = state()
+        assert sorted(s) == list(range(16)), s
+        for v, c in zip(s, cell):          # empty cell = board colour, numbers on white
+            assert int(c.g("backgroundColor")) == (0x31A6 if v == 0 else 0xFFFF), (s, v)
+
+    def show():
+        s = state()
+        return "\n".join(" ".join(f"{v:3d}" if v else "  ." for v in s[r * 4:r * 4 + 4])
+                         for r in range(4))
+
+    def solved():
+        return paths["/logic/post/Solved"].g("out", False)
+
+    def moves():
+        return paths["/logic/post/CntF"].g("out")
+
+    def press(k):
+        cell[k].v["touch"] = True
+        step(2)
+        cell[k].v["touch"] = False
+        step(2)
+
+    step(3)
+    assert state() == goal, "boot did not load the solved board: %s" % (state(),)
+    step(120)
+    check()
+    print("after shuffle:\n" + show())
+    assert state() != goal and not solved() and moves() == 0
+
+    z = state().index(0)
+    far = next(k for k in range(16) if abs(k // 4 - z // 4) + abs(k % 4 - z % 4) >= 2)
+    before = state()
+    press(far)
+    assert state() == before, "non-adjacent cell moved"
+    press(z)
+    assert state() == before, "pressing the empty cell changed the board"
+    n = z - 1 if z % 4 else z + 1
+    v = before[n]
+    press(n)
+    s = state()
+    assert s[n] == 0 and s[z] == v and moves() == 1, "valid move failed"
+    cell[z].v["touch"] = True              # hold: exactly one move back
+    step(10)
+    cell[z].v["touch"] = False
+    step(2)
+    assert state() == before and moves() == 2, "hold did not move exactly once"
+    check()
+
+    path = astar(state())
+    assert path is not None, "solver gave up"
+    print("solving in", len(path), "presses")
+    for k in path:
+        press(k)
+    step(5)
+    print(show())
+    check()
+    assert state() == goal and solved(), "solved flag not set"
+    print("SOLVED flag OK, moves:", moves())
+
+    paths["/ox/Game/Shuffle"].v["touch"] = True
+    step(2)
+    paths["/ox/Game/Shuffle"].v["touch"] = False
+    step(120)
+    check()
+    assert state() != goal and not solved() and moves() == 0
+    print("re-shuffle OK")
+
+
 if __name__ == "__main__":
     import sys
-    main_solver() if "--solver" in sys.argv else main()
+    if "--solver" in sys.argv:
+        main_solver()
+    elif "--v2" in sys.argv:
+        main_v2()
+    else:
+        main()