test(mutants): stage3-w12 guard follows the renamed #649 contract test

The guard pattern "Labs iso is presentation-only" matched no test after #649
renamed it, so node --test ran the file with zero subtests and the mutant
survived (Validate 36151140394, shard 3/6). Point it at the test that still
asserts params.getAll('hp_alpha').

Issue: #649
User-Visible: no

scripts/mutation-registry.mjs

@@ -10452,7 +10452,7 @@ const MUTANT_DEFINITIONS = [
   },
   {
     id: 'stage3-w12-separate-alpha-url-key-restored',
-    guard: 'node --test --test-name-pattern="Labs iso is presentation-only" '
+    guard: 'node --test --test-name-pattern="2.5D is the General settings switch, presentation-only" '
       + 'test/isometric-contract.test.mjs',
     because: 'W12: Stage 4 shares the one permanent hp_alpha switch; a feature-specific URL '
       + 'key or expiry must not return (#570)',