document property
The decoded body, re-encoded — never a re-serialised model.
Neither transport port ever exposes raw wire bytes: both get() and
getConditional() hand back an already-decoded Map<String, dynamic>,
so there is no original JSON string in this package to store. This is
jsonEncode() of that same decoded map, which is what makes it safe: a
key PanelSchema.fromJson does not yet recognise is still in that map
and survives the round trip. Encoding the model instead would let
this package's own types silently become the cache's schema and drop
such a key on write, never to be recovered.
Key order or escaping may differ from what the server originally sent,
and that is inert: etag is never recomputed or compared against
these bytes — it is an opaque token, stored beside the document and
echoed back in If-None-Match.
Implementation
final String document;