🧪 Add tests for autonomyColor theme utility

[toreleon]

🎯 What: The missing tests for the autonomyColor utility function in src/tui/lib/theme.ts have been added.
📊 Coverage: The three main conditional paths are now tested: "auto", "confirm", and all other fallbacks like "off".
✨ Result: Test coverage improved with the 4 new test cases successfully passing using vitest.

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PR created automatically by Jules for task 12611464612767364219 started by @toreleon

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