🧪 Add test for action resolving to a function

[johnstrand]

🎯 What: Added missing edge case test for action resolving to a function in Squawk.action.test.ts. This tests the functionality where dispatchUpdate correctly evaluates a function if an action returns one.
📊 Coverage: Covered the case where store.action() returns a function that resolves to the store updates.
✨ Result: Improved test coverage by covering the code path in dispatchUpdate where a function instead of an object is returned from an action.

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PR created automatically by Jules for task 3646280413755413039 started by @johnstrand

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