Add live debugger frontend and mutex stall recovery (#383)

src/SharpEmu.Core/Cpu/CpuDispatcher.cs

@@ -3,6 +3,7 @@
 
 using System.Buffers.Binary;
 using System.Text;
+using SharpEmu.Core.Cpu.Debugging;
 using SharpEmu.Core.Cpu.Native;
 using SharpEmu.Core.Loader;
 using SharpEmu.Core.Memory;
@@ -272,7 +273,23 @@ public sealed class CpuDispatcher : ICpuDispatcher, IDisposable
             entryFrameDiagnostic,
             Environment.NewLine,
             "CpuEngine: native-only");
+        // Frame boundaries an attached debugger observes; null hook = a branch.
+        var debugHook = executionOptions.DebugHook;
+        var debugFrame = debugHook is null
+            ? null
+            : new CpuContextDebugFrame(
+                frameKind == EntryFrameKind.ProcessEntry
+                    ? CpuDebugFrameKind.ProcessEntry
+                    : CpuDebugFrameKind.ModuleInitializer,
+                entryPoint,
+                processImageName,
+                context,
+                effectiveImportStubs);
+        debugHook?.OnFrameEnter(debugFrame!);
+
         _nativeCpuBackend ??= new DirectExecutionBackend(_moduleManager);
+        // Let backend stall reports reference the same frame as entry.
+        (_nativeCpuBackend as DirectExecutionBackend)?.SetActiveDebugFrame(debugFrame);
         if (_nativeCpuBackend.TryExecute(
                 context,
                 entryPoint,
@@ -282,6 +299,7 @@ public sealed class CpuDispatcher : ICpuDispatcher, IDisposable
                 executionOptions,
                 out var nativeResult))
         {
+            debugHook?.OnFrameExit(debugFrame!, nativeResult);
             LastSessionSummary = new CpuSessionSummary(
                 nativeResult,
                 nativeResult == OrbisGen2Result.ORBIS_GEN2_OK
@@ -296,6 +314,8 @@ public sealed class CpuDispatcher : ICpuDispatcher, IDisposable
             return nativeResult;
         }
 
+        debugHook?.OnFrameExit(debugFrame!, OrbisGen2Result.ORBIS_GEN2_ERROR_NOT_IMPLEMENTED);
+
         var backendName = string.IsNullOrWhiteSpace(_nativeCpuBackend.BackendName)
             ? "native-backend"
             : _nativeCpuBackend.BackendName;