🧪 Add tests for useSquawk hook

[johnstrand]

🎯 What: The useSquawk hook was previously untested.
📊 Coverage: The new tests in src/__tests__/Squawk.useSquawk.test.ts now cover:

• Initial state returned correctly.
• Proxy context tracking (happy path).
• Explicit context tracking (happy path).
• Subscription to global state updates (happy path).
• Unsubscribing when unmounting to avoid setting state on unmounted component (edge case).
  ✨ Result: Test coverage is significantly improved by mocking React hooks directly without introducing problematic peer dependencies, providing safety during refactoring.

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PR created automatically by Jules for task 6254903761346063552 started by @johnstrand

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