fix(party-mode): decode subprocess JSON as UTF-8 on Windows (#2687)

src/core-skills/bmad-party-mode/scripts/resolve_party.py

@@ -46,7 +46,9 @@ except ImportError:  # pragma: no cover - guarded for <3.11
 def _run_json(cmd):
     """Run a resolver script and parse its JSON stdout. None on any failure."""
     try:
-        out = subprocess.run(cmd, capture_output=True, text=True, timeout=60)
+        out = subprocess.run(
+            cmd, capture_output=True, text=True, encoding="utf-8", timeout=60
+        )
     except (OSError, subprocess.SubprocessError):
         return None
     if out.returncode != 0 or not out.stdout.strip():