add units for ollama

[JaredforReal]

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[Copilot]

Pull request overview

Adds unit test coverage for the existing Ollama /api/generate integration path in OCRClient, ensuring request conversion and response parsing behave correctly alongside the default OpenAI-compatible mode.

Changes:

• Add unit tests validating OCRApiConfig.api_mode defaults and OCRClient mode selection.
• Add unit tests for _convert_to_ollama_generate() covering prompt/image extraction and option mapping.
• Add unit tests for OCRClient.process() and OCRClient.connect() behavior in both ollama_generate and openai modes.

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