gdb: More cleanup changes

- Move the message handler into its debugger class part,
- Move all message types into one file and collapse 3 of the ones with no data into a generic, stateless message with a single property being its type,
- Add an Fpscr helper property on IExecutionContext along with a comment about what Fpscr is (similar to the other registers in there)
- Moved the Rcmd helpers (such as GetRegisters, GetMinidump, etc) into a dedicated Debugger class part,
- Fixed the double-collection (ToArray being called twice) in GetThreadUids & GetThread in KProcess

src/Ryujinx.HLE/Debugger/Debugger.Rcmd.cs

@@ -0,0 +1,103 @@
+using Ryujinx.Common.Logging;
+using Ryujinx.HLE.HOS.Kernel.Process;
+using System;
+using System.Text;
+
+namespace Ryujinx.HLE.Debugger
+{
+    public partial class Debugger
+    {
+        public string GetStackTrace()
+        {
+            if (GThread == null)
+                return "No thread selected\n";
+
+            return Process?.Debugger?.GetGuestStackTrace(DebugProcess.GetThread(GThread.Value)) ?? "No application process found\n"; 
+        }
+
+        public string GetRegisters()
+        {
+            if (GThread == null)
+                return "No thread selected\n";
+
+            return Process?.Debugger?.GetCpuRegisterPrintout(DebugProcess.GetThread(GThread.Value)) ?? "No application process found\n";
+        }
+
+        public string GetMinidump()
+        {
+            var response = new StringBuilder();
+            response.AppendLine("=== Begin Minidump ===\n");
+            response.AppendLine(GetProcessInfo());
+
+            foreach (var thread in GetThreads())
+            {
+                response.AppendLine($"=== Thread {thread.ThreadUid} ===");
+                try
+                {
+                    string stackTrace = Process.Debugger.GetGuestStackTrace(thread);
+                    response.AppendLine(stackTrace);
+                }
+                catch (Exception e)
+                {
+                    response.AppendLine($"[Error getting stack trace: {e.Message}]");
+                }
+
+                try
+                {
+                    string registers = Process.Debugger.GetCpuRegisterPrintout(thread);
+                    response.AppendLine(registers);
+                }
+                catch (Exception e)
+                {
+                    response.AppendLine($"[Error getting registers: {e.Message}]");
+                }
+            }
+
+            response.AppendLine("=== End Minidump ===");
+
+            Logger.Info?.Print(LogClass.GdbStub, response.ToString());
+            return response.ToString();
+        }
+
+        public string GetProcessInfo()
+        {
+            try
+            {
+                if (Process is not { } kProcess)
+                    return "No application process found\n";
+
+                var sb = new StringBuilder();
+
+                sb.AppendLine($"Program Id:  0x{kProcess.TitleId:x16}");
+                sb.AppendLine($"Application: {(kProcess.IsApplication ? 1 : 0)}");
+                sb.AppendLine("Layout:");
+                sb.AppendLine(
+                    $"  Alias: 0x{kProcess.MemoryManager.AliasRegionStart:x10} - 0x{kProcess.MemoryManager.AliasRegionEnd - 1:x10}");
+                sb.AppendLine(
+                    $"  Heap:  0x{kProcess.MemoryManager.HeapRegionStart:x10} - 0x{kProcess.MemoryManager.HeapRegionEnd - 1:x10}");
+                sb.AppendLine(
+                    $"  Aslr:  0x{kProcess.MemoryManager.AslrRegionStart:x10} - 0x{kProcess.MemoryManager.AslrRegionEnd - 1:x10}");
+                sb.AppendLine(
+                    $"  Stack: 0x{kProcess.MemoryManager.StackRegionStart:x10} - 0x{kProcess.MemoryManager.StackRegionEnd - 1:x10}");
+
+                sb.AppendLine("Modules:");
+                var debugger = kProcess.Debugger;
+                if (debugger != null)
+                {
+                    foreach (HleProcessDebugger.Image image in debugger.GetLoadedImages())
+                    {
+                        ulong endAddress = image.BaseAddress + image.Size - 1;
+                        sb.AppendLine($"  0x{image.BaseAddress:x10} - 0x{endAddress:x10} {image.Name}");
+                    }
+                }
+
+                return sb.ToString();
+            }
+            catch (Exception e)
+            {
+                Logger.Error?.Print(LogClass.GdbStub, $"Error getting process info: {e.Message}");
+                return $"Error getting process info: {e.Message}\n";
+            }
+        }
+    }
+}