🧹 Remove unused Optional import in semantic.py

[dioncx]

🎯 What: Removed the unused Optional type import from json_memory/semantic.py line 10.
💡 Why: Standard unused import cleanup to improve code maintainability and cleanliness.
✅ Verification: Verified by running the test suite with python3 -m pytest tests/ which completed successfully with 334 passed tests. Unintended test generated files were carefully excluded from the commit.
✨ Result: A cleaner import section without unused references.

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PR created automatically by Jules for task 5589396236902255403 started by @dioncx

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