Optional seen: Map<object, string>cyclic reference guard (Map of object → placeholder)
Optional symbols: booleanSerialises an arbitrary JavaScript value into the uniform SerializedValue format.
Handles primitives, Date, RegExp, Buffer, Error, arrays, and plain objects.
Objects with prototype !== Object.prototype are treated as opaque and returned as {t: 'ref'}.
When stripRequestEnabled is set, the request key is skipped (Axios HTTP internals).
value to serialise