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>

build.py

@@ -1,4 +1,4 @@
-"""Builds aspirin(.sax/_solver.sax) -> .sab and packages app-ORION-<name>.zip for simulatorLauncher.exe.
+"""Builds aspirin(.sax/_solver.sax/V2.sax) -> .sab and packages app-ORION-<name>.zip for simulatorLauncher.exe.
 
 Zip layout matches the launcher's ExampleApp backups:
   app.sax, device/app.sab, device/kits.scode, device/fonts/*.oxfl, fontBankXL/*.oxfl
@@ -22,9 +22,24 @@ env = dict(os.environ, sedona_home=SEDONA)
 with zipfile.ZipFile(EXAMPLE) as src:
     scode = src.read("device/kits.scode")
 
-for name, args in (("aspirin", []), ("aspirin_solver", ["--solver"])):
-    subprocess.check_call([sys.executable, "gen_aspirin.py"] + args)
-    subprocess.check_call([os.path.join(SEDONA, "bin", "sedonac.exe"), f"{name}.sax"], env=env)
+JAVA = r"C:\Niagara\Niagara-4.15.1.16\jre\bin\java.exe"   # fallback when sedonac.exe finds no JVM
+
+
+def sedonac(sax):
+    if subprocess.call([os.path.join(SEDONA, "bin", "sedonac.exe"), sax], env=env) == 0:
+        return
+    lib = os.path.join(SEDONA, "lib")
+    subprocess.check_call([JAVA, f"-Dsedona.home={SEDONA}", "-cp",
+                           os.pathsep.join([os.path.join(lib, "sedonac.jar"),
+                                            os.path.join(lib, "sedona.jar")]),
+                           "sedonac.Main", sax])
+
+
+for name, gen in (("aspirin", ["gen_aspirin.py"]),
+                  ("aspirin_solver", ["gen_aspirin.py", "--solver"]),
+                  ("aspirinV2", ["gen_aspirinV2.py"])):
+    subprocess.check_call([sys.executable] + gen)
+    sedonac(f"{name}.sax")
     out = f"app-ORION-{name}.zip"
     with zipfile.ZipFile(out, "w", zipfile.ZIP_DEFLATED) as z:
         z.write(f"{name}.sax", "app.sax")