build llama.cpp embedding url path by appending instead of overwriting (#5178) * build llama.cpp embedding url path by appending instead of overwriting When using a llama-swap frontend, this allows choosing the embedding model by path; for instance, with the secondary embedding endpoint URL configured to http://127.0.0.1:5001/upstream/emb-model to pick the "emb-model" model. With this approach, the same llama-swap instance can be used to serve both the main LLM and the embedding model from local llama-server commands. * Trim trailing v1 from URL --------- Co-authored-by: Cohee <18619528+Cohee1207@users.noreply.github.com>