SimpleChatTC:DataStore:FuncCallArgs: Any type not supported

So mention that may be ai can send complex objects in stringified
form. Rather once type of value is set to string, ai should normally
do it, but no harm is hinting.

tools/server/public_simplechat/tooldb.mjs

@@ -22,7 +22,7 @@ let dsget_meta = {
                         "description": "The key whose value should be returned."
                     }
                 },
-                "required": [ "key" ],
+                "required": ["key"],
             }
         }
     }
@@ -54,8 +54,8 @@ let dsset_meta = {
                         "description": "The key under which to store the value."
                     },
                     "value": {
-                        "type": "any",
-                        "description": "The value to store. Can be any JSON-serialisable type."
+                        "type": "string",
+                        "description": "The value to store, complex objects could be passed in JSON Stringified format."
                     }
                 },
                 "required": ["key", "value"]