fix: raise from exceptions

semantic_router/encoders/cohere.py

semantic_router/encoders/fastembed.py

semantic_router/encoders/openai.py

semantic_router/encoders/zure.py

semantic_router/llms/cohere.py

semantic_router/llms/openai.py

semantic_router/llms/openrouter.py

semantic_router/utils/llm.py