Fix ollama model selection for ollama targets

[stevemason]

I had an issue when using ollama targets where I could only use models which had been manually added to the hardcoded list of supported models (_OPTION_MAP). Example error output below, where the unknown key is listed as a valid key:

Error: Unknown Ollama key 'llama3.1:8b'. Valid keys: gemma3:1b, gemma3:4b, tinyllama:1.1b, nomic-embed-text:v1.5, llama3.1:8b

Given that ollama is queried for which models are available, I think it makes sense to use this query as the basis for which models are available for ollama targets.

I've modified the code to reflect this, and also removed references to _OPTION_MAP in the ollama_api module.

I also saw that when doing 'spikee list targets' it listed the first model as the default, so I've fixed the bahaviour to reflect this for ollama targets.

I've kept _DEFAULT_KEY for now to make this change easier, though I think it could probably be removed in the future.

Also, adding .sonar folder to .gitignore is helpful for those using sonarqube

[kyuz0]

Thank you for contributing this.