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/Windows/RemoteWindow.cs

@@ -0,0 +1,147 @@
+using System.Runtime.InteropServices;
+using System.Text;
+using WhiteMagic.Native;
+
+namespace WhiteMagic.Windows;
+
+/// <summary>
+/// Wrapper around a native window handle that supports querying and mutating
+/// common window properties.
+/// </summary>
+public sealed class RemoteWindow
+{
+    private const int MaxTextLength = 512;
+
+    /// <summary>Creates a wrapper for the specified window handle.</summary>
+    public RemoteWindow(IntPtr handle)
+    {
+        if (handle == IntPtr.Zero)
+            throw new ArgumentException("Window handle cannot be zero.", nameof(handle));
+
+        Handle = handle;
+    }
+
+    /// <summary>The native window handle.</summary>
+    public IntPtr Handle { get; }
+
+    /// <summary>The window class name.</summary>
+    public string ClassName => GetClassName(Handle);
+
+    /// <summary>The current window text.</summary>
+    public string Text => GetWindowText(Handle);
+
+    /// <summary>The process identifier that owns the window.</summary>
+    public uint ProcessId => GetWindowProcessId(Handle);
+
+    /// <summary>Gets or sets the window title.</summary>
+    public string Title
+    {
+        get => GetWindowText(Handle);
+        set
+        {
+            if (value is null)
+                throw new ArgumentNullException(nameof(value));
+
+            if (!NativeMethods.SetWindowTextW(Handle, value))
+            {
+                int error = Marshal.GetLastPInvokeError();
+                throw new InvalidOperationException(
+                    $"SetWindowText failed for window {Handle} with error {error}.");
+            }
+        }
+    }
+
+    /// <summary><see langword="true"/> if this window is currently the foreground window.</summary>
+    public bool IsActive => NativeMethods.GetForegroundWindow() == Handle;
+
+    /// <summary>Moves and resizes the window.</summary>
+    public bool MoveResize(int x, int y, int width, int height)
+    {
+        return NativeMethods.SetWindowPos(
+            Handle,
+            NativeMethods.HwndTop,
+            x,
+            y,
+            width,
+            height,
+            NativeMethods.SwpShowWindow);
+    }
+
+    /// <summary>Activates the window and brings it to the foreground.</summary>
+    public bool Activate()
+    {
+        IntPtr foreground = NativeMethods.GetForegroundWindow();
+        uint targetThread = NativeMethods.GetWindowThreadProcessId(Handle, out _);
+        uint foregroundThread = NativeMethods.GetWindowThreadProcessId(foreground, out _);
+
+        if (targetThread == 0)
+            return false;
+
+        if (targetThread == foregroundThread)
+            return NativeMethods.SetForegroundWindow(Handle);
+
+        if (!NativeMethods.AttachThreadInput(foregroundThread, targetThread, true))
+            return false;
+
+        try
+        {
+            return NativeMethods.SetForegroundWindow(Handle);
+        }
+        finally
+        {
+            NativeMethods.AttachThreadInput(foregroundThread, targetThread, false);
+        }
+    }
+
+    /// <summary>Flashes the window in the caption and taskbar button.</summary>
+    public bool Flash()
+    {
+        var info = new FlashWindowInfo
+        {
+            cbSize = (uint)Marshal.SizeOf<FlashWindowInfo>(),
+            hwnd = Handle,
+            dwFlags = NativeMethods.FlashwAll,
+            uCount = 3,
+            dwTimeout = 0,
+        };
+
+        return NativeMethods.FlashWindowEx(ref info);
+    }
+
+    public override string ToString()
+    {
+        var sb = new StringBuilder();
+        sb.Append("RemoteWindow(");
+        sb.Append(Handle.ToString("X"));
+        sb.Append(", ");
+        sb.Append(ClassName);
+        sb.Append(")");
+        return sb.ToString();
+    }
+
+    private static string GetClassName(IntPtr handle)
+    {
+        var buffer = new char[256];
+        int length = NativeMethods.GetClassNameW(handle, buffer, buffer.Length);
+        if (length <= 0)
+            return string.Empty;
+
+        return new string(buffer, 0, length);
+    }
+
+    private static string GetWindowText(IntPtr handle)
+    {
+        var buffer = new char[MaxTextLength];
+        int length = NativeMethods.GetWindowTextW(handle, buffer, buffer.Length);
+        if (length <= 0)
+            return string.Empty;
+
+        return new string(buffer, 0, length);
+    }
+
+    private static uint GetWindowProcessId(IntPtr handle)
+    {
+        NativeMethods.GetWindowThreadProcessId(handle, out uint processId);
+        return processId;
+    }
+}