🛡️ Sentinel: Fix uninitialized memory leak in PersistenceLayer

[ightevenmckane187]

🛡️ Sentinel: Fix syntax error and replace Buffer.allocUnsafe with Buffer.alloc in PersistenceLayer.ts to eliminate uninitialized heap memory disclosure risks.

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PR created automatically by Jules for task 4091084624939006629 started by @ightevenmckane187

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