fix(vmem): use ConcurrentDictionary for _pageProtections to prevent race corruption (#823)

src/SharpEmu.Core/Memory/PhysicalVirtualMemory.cs

@@ -1,6 +1,7 @@
 // Copyright (C) 2026 SharpEmu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
+using System.Collections.Concurrent;
 using System.Runtime.InteropServices;
 using SharpEmu.Core.Loader;
 using SharpEmu.HLE;
@@ -18,7 +19,7 @@ public sealed unsafe class PhysicalVirtualMemory : IVirtualMemory, IGuestMemoryA
     private readonly object _allocationSearchHintGate = new();
     private readonly List<MemoryRegion> _regions = new();
     private readonly Dictionary<(ulong DesiredAddress, ulong Alignment, bool Executable), ulong> _allocationSearchHints = new();
-    private readonly Dictionary<ulong, ProgramHeaderFlags> _pageProtections = new();
+    private readonly ConcurrentDictionary<ulong, ProgramHeaderFlags> _pageProtections = new();
     private bool _disposed;
 
     [ThreadStatic]