Sends an embeddings request to the Mistral API.

Arguments:

• model : String — the model name for embedding (e.g., "mistral-embed")
• input : Array(String) — list of texts to be embedded

Returns:

• EmbeddingResponse — includes vectors for each input

Raises:

• ArgumentError if model is empty
• RuntimeError via handle_error if the response indicates an error

Example:

input = [
  "Crystal is a fast language.",
  "Mistral provides language models.",
]

client = CrystalMistral::Client.new
response = client.embeddings(
  model: "mistral-embed",
  input: input
)

response.data.each_with_index do |embedding, i|
  puts "Embedding for input ##{i}: #{embedding.embedding[0..4]}..."
end