Add --print-rules-info CLI flag for host cache freshness lookup

rcjav/cli.py

@@ -409,6 +409,10 @@ def main():
                          "using the current ID extraction rules. No rclone calls — "
                          "fast path for picking up rule changes without re-scanning. "
                          "Outputs JSON when --format json, plain otherwise.")
+    ap.add_argument("--print-rules-info", action="store_true",
+                    help="Print cache contract version constants and current "
+                         "rules signature as JSON, then exit. Used by the native-"
+                         "messaging host to surface cache freshness in the UI.")
     ap.add_argument("--basic", action="store_true",
                     help="Plain text output, no rich tables/panels/progress bars. "
                          "Useful for piping or low-bandwidth terminals.")
@@ -485,6 +489,18 @@ def main():
         args.catalog = list(DEFAULT_CATALOG)
 
     # --library-issues: read-only cache scan for non-canonical filenames.
+    # --print-rules-info: report current cache contract constants + rules signature.
+    if args.print_rules_info:
+        from rcjav.cache import CACHE_SCHEMA_VERSION, ID_RULES_VERSION
+        from rcjav.ids import current_rules_signature
+        print(json.dumps({
+            "ok": True,
+            "cache_schema": CACHE_SCHEMA_VERSION,
+            "id_rules": ID_RULES_VERSION,
+            "id_rules_signature": current_rules_signature(),
+        }))
+        sys.exit(0)
+
     # --reextract: rebuild jav_id values from current rules without re-scanning.
     if args.reextract:
         from rcjav.ids import current_rules_signature