llama : rework embeddings logic (#14208)
* llama : rework embeddings logic
ggml-ci
* cont : fix rerank
ggml-ci
* cont : engrish [no ci]
* cont : fix rerank
ggml-ci
* server : support both embeddings and completions with single model
ggml-ci
* cont : avoid embeddings_org
ggml-ci