Implement core diagnostic memory layer, execution helpers, and high-level facade slices

Implemented:
- Core: UTF-16 ReadString boundary/alignment fix, target bitness and process id on MemoryBase
- function interception: PatchManager, DetourManager, InstructionAnalyzer, MainThreadDispatcher
- Execution: BackgroundTaskExecutor, InProcessInvoker
- High-level: Magic facade, RemotePointer, async wrappers
- Discovery/external code loading/Window groundwork (PEB/TEB, pattern scanning, raw allocations, DLL external code loading, window/input)

Tests: 180 passing, 4 integration/interactive tests skipped.

WhiteMagic/Magic.cs

@@ -0,0 +1,62 @@
+using System.Diagnostics;
+using Process = System.Diagnostics.Process;
+using WhiteMagic.Execution;
+using WhiteMagic.Hooking;
+
+namespace WhiteMagic;
+
+/// <summary>
+/// High-level entry point for a WhiteMagic session. Opens a process, exposes the
+/// memory reader, execution tiers, hooking managers, and the <see cref="RemotePointer"/>
+/// indexer.
+/// </summary>
+public sealed class Magic : IDisposable
+{
+    /// <summary>The underlying memory reader for this session.</summary>
+    public MemoryBase Memory { get; }
+
+    /// <summary>Out-of-process execution via <c>CreateRemoteThread</c>.</summary>
+    public RemoteThreadExecutor RemoteThread { get; }
+
+    /// <summary>Named byte-patch manager.</summary>
+    public PatchManager PatchManager => Memory.PatchManager;
+
+    /// <summary>Inline-detour manager (in-process only).</summary>
+    public DetourManager DetourManager => Memory.DetourManager;
+
+    private Magic(MemoryBase memory)
+    {
+        Memory = memory;
+        RemoteThread = new RemoteThreadExecutor(memory);
+    }
+
+    /// <summary>Opens an external process for reading, writing, and execution.</summary>
+    public static Magic Open(System.Diagnostics.Process process)
+    {
+        return new Magic(new ExternalReader(process));
+    }
+
+    /// <summary>Creates an in-process session for the current process.</summary>
+    public static Magic OpenInProcess()
+    {
+        return new Magic(new InProcessReader());
+    }
+
+    /// <summary>
+    /// Creates a main-thread pump that hooks the per-frame function at
+    /// <paramref name="frameAddress"/>.
+    /// </summary>
+    public MainThreadPump CreateMainThreadPump(IntPtr frameAddress)
+    {
+        return new MainThreadPump(DetourManager, frameAddress);
+    }
+
+    /// <summary>Returns a <see cref="RemotePointer"/> at <paramref name="address"/>.</summary>
+    public RemotePointer this[IntPtr address] => new RemotePointer(Memory, address);
+
+    /// <inheritdoc />
+    public void Dispose()
+    {
+        Memory.Dispose();
+    }
+}