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.

WhiteMagicTest/ThreadEnvironment/ManagedTebTests.cs

@@ -0,0 +1,23 @@
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.ThreadEnvironment;
+using Xunit;
+
+namespace WhiteMagicTest.ThreadEnvironment;
+
+public sealed class ManagedTebTests
+{
+    [Fact]
+    public void Read_current_thread_teb_fields_returns_plausible_values()
+    {
+        using var magic = Magic.OpenInProcess();
+        using var teb = new ManagedTeb(magic.Memory, (int)NativeMethods.GetCurrentThreadId());
+
+        Assert.NotEqual(IntPtr.Zero, teb.ReadTebAddress());
+        Assert.NotEqual(IntPtr.Zero, teb.ReadStackBase());
+        Assert.NotEqual(IntPtr.Zero, teb.ReadStackLimit());
+
+        // The stack grows down, so the base is above the limit on x86/x64.
+        Assert.True((nuint)teb.ReadStackBase() > (nuint)teb.ReadStackLimit());
+    }
+}