Add Llama support to Inference Plugin

[Jan-Kazlouski-elastic]

Creation of new Llama inference provider integration allowing text_embedding, completion (both streaming and non-streaming) and chat_completion (only streaming) to be executed as part of inference API.

Changes were tested locally against next models:

• all-MiniLM-L6-v2 (text embedding)
• llama3.2:3b (completion & chat_completion)

For testing ollama service was used.

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