Use is_matryoshka to denote whether a model is compatible with Matryoshka Representation Learning (MRL).

I come from the vllm community, and recently vllm has added [support for Matryoshka Representation Learning (MRL)](https://github.com/vllm-project/vllm/pull/16331).

Not all embeddings models support MRL. Changing the output dimension for models that do not support MRL will lead to poor results.

We hope that the open source community will adopt the terms “is_matryoshka ” or “matryoshka_dimensions ” to denote whether a model is compatible with Matryoshka Representation Learning (MRL).

config.json

@@ -22,5 +22,6 @@
   "transformers_version": "4.39.3",
   "type_vocab_size": 2,
   "use_cache": true,
+  "is_matryoshka": true,
   "vocab_size": 30522
 }