IPC refactor part 3+4: New server HIPC message processor (#4188)

* IPC refactor part 3 + 4: New server HIPC message processor with source generator based serialization

* Make types match on calls to AlignUp/AlignDown

* Formatting

* Address some PR feedback

* Move BitfieldExtensions to Ryujinx.Common.Utilities and consolidate implementations

* Rename Reader/Writer to SpanReader/SpanWriter and move to Ryujinx.Common.Memory

* Implement EventType

* Address more PR feedback

* Log request processing errors since they are not normal

* Rename waitable to multiwait and add missing lock

* PR feedback

* Ac_K PR feedback

Ryujinx.Horizon/Sdk/Sm/ServiceName.cs

@@ -0,0 +1,98 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Horizon.Sdk.Sm
+{
+    [StructLayout(LayoutKind.Sequential, Pack = 1)]
+    struct ServiceName
+    {
+        public static ServiceName Invalid { get; } = new ServiceName(0);
+
+        public bool IsInvalid => Packed == 0;
+
+        public int Length => sizeof(ulong);
+
+        public ulong Packed { get; }
+
+        public byte this[int index]
+        {
+            get
+            {
+                if ((uint)index >= sizeof(ulong))
+                {
+                    throw new IndexOutOfRangeException();
+                }
+
+                return (byte)(Packed >> (index * 8));
+            }
+        }
+
+        private ServiceName(ulong packed)
+        {
+            Packed = packed;
+        }
+
+        public static ServiceName Encode(string name)
+        {
+            ulong packed = 0;
+
+            for (int index = 0; index < sizeof(ulong); index++)
+            {
+                if (index < name.Length)
+                {
+                    packed |= (ulong)(byte)name[index] << (index * 8);
+                }
+                else
+                {
+                    break;
+                }
+            }
+
+            return new ServiceName(packed);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return obj is ServiceName serviceName && serviceName.Equals(this);
+        }
+
+        public bool Equals(ServiceName other)
+        {
+            return other.Packed == Packed;
+        }
+
+        public override int GetHashCode()
+        {
+            return Packed.GetHashCode();
+        }
+
+        public static bool operator ==(ServiceName lhs, ServiceName rhs)
+        {
+            return lhs.Equals(rhs);
+        }
+
+        public static bool operator !=(ServiceName lhs, ServiceName rhs)
+        {
+            return !lhs.Equals(rhs);
+        }
+
+        public override string ToString()
+        {
+            string name = string.Empty;
+
+            for (int index = 0; index < sizeof(ulong); index++)
+            {
+                byte character = (byte)(Packed >> (index * 8));
+
+                if (character == 0)
+                {
+                    break;
+                }
+
+                name += (char)character;
+            }
+
+            return name;
+        }
+    }
+}