🧪 Add tests for SmartMemory encryption methods

[dioncx]

• 🎯 What: The untested SmartMemory.enable_encryption method and related methods (disable_encryption, remember_encrypted, recall_decrypted) now have comprehensive tests.
• 📊 Coverage: Test coverage handles toggling encryption state, storing and retrieving encrypted data, error handling when encryption is missing, defaults, and recalling unencrypted values gracefully.
• ✨ Result: Prevents regressions in a crucial security toggle and increases test coverage for SmartMemory.

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PR created automatically by Jules for task 2703650911655387368 started by @dioncx

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