feat(simulation): add Worker AI polygon runtime and terrain navigation

src/k1link/artifacts.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import hashlib
 import json
 import os
 import tempfile
@@ -8,6 +9,14 @@ from pathlib import Path
 from typing import Any
 
 
+def canonical_json_sha256(value: object) -> str:
+    """Platform-independent identity for shared Core/Worker JSON contracts."""
+    payload = json.dumps(
+        value, ensure_ascii=False, allow_nan=False, separators=(",", ":"), sort_keys=True
+    ).encode("utf-8")
+    return hashlib.sha256(payload).hexdigest()
+
+
 def utc_now_iso() -> str:
     """Return a stable UTC timestamp for manifests and capture artifacts."""
     return datetime.now(UTC).isoformat(timespec="milliseconds").replace("+00:00", "Z")