Initial commit: LegacyForge mod loader for Minecraft Legacy Edition

SKSE-style external mod loader with zero game source modifications.
- LegacyForge.Launcher: C# console app that injects runtime DLL into game process
- LegacyForgeRuntime: C++ DLL with PDB symbol resolution, MinHook function hooking, and .NET CoreCLR hosting
- LegacyForge.Core: C# mod discovery and lifecycle management
- LegacyForge.API: Fabric-style mod API with namespaced string IDs, fluent property builders, and event system
- ExampleMod: Sample mod demonstrating block/item registration

LegacyForge.Launcher/Program.cs

@@ -0,0 +1,83 @@
+namespace LegacyForge.Launcher;
+
+class Program
+{
+    private const string ConfigFile = "legacyforge.json";
+    private const string RuntimeDll = "LegacyForgeRuntime.dll";
+
+    static int Main(string[] args)
+    {
+        Console.WriteLine("╔══════════════════════════════════╗");
+        Console.WriteLine("║         LegacyForge v1.0        ║");
+        Console.WriteLine("║  Mod Loader for MC Legacy Edition║");
+        Console.WriteLine("╚══════════════════════════════════╝");
+        Console.WriteLine();
+
+        try
+        {
+            var config = Config.Load(ConfigFile);
+
+            if (args.Length > 0 && File.Exists(args[0]))
+            {
+                config.GameExePath = args[0];
+                config.Save(ConfigFile);
+            }
+
+            if (string.IsNullOrEmpty(config.GameExePath) || !File.Exists(config.GameExePath))
+            {
+                Console.Write("Enter path to MinecraftLegacy.exe: ");
+                string? input = Console.ReadLine()?.Trim().Trim('"');
+
+                if (string.IsNullOrEmpty(input) || !File.Exists(input))
+                {
+                    Console.Error.WriteLine("Error: Invalid path or file not found.");
+                    return 1;
+                }
+
+                config.GameExePath = Path.GetFullPath(input);
+                config.Save(ConfigFile);
+                Console.WriteLine($"Saved game path to {ConfigFile}");
+            }
+
+            if (!File.Exists(RuntimeDll))
+            {
+                Console.Error.WriteLine($"Error: {RuntimeDll} not found in current directory.");
+                Console.Error.WriteLine("Make sure the runtime DLL is next to LegacyForge.exe.");
+                return 1;
+            }
+
+            string modsDir = Path.Combine(AppContext.BaseDirectory, "mods");
+            if (!Directory.Exists(modsDir))
+            {
+                Directory.CreateDirectory(modsDir);
+                Console.WriteLine($"Created mods/ directory at {modsDir}");
+            }
+
+            int modCount = Directory.GetFiles(modsDir, "*.dll").Length;
+            Console.WriteLine($"Found {modCount} mod(s) in mods/");
+            Console.WriteLine($"Launching {Path.GetFileName(config.GameExePath)}...");
+
+            var process = Injector.LaunchSuspended(config.GameExePath);
+            Console.WriteLine($"Game process created (PID: {process.ProcessId}), injecting runtime...");
+
+            Injector.InjectDll(process, RuntimeDll);
+            Console.WriteLine("LegacyForgeRuntime.dll injected successfully.");
+
+            Injector.ResumeProcess(process);
+            Console.WriteLine("Game resumed. LegacyForge is active.");
+            Console.WriteLine();
+            Console.WriteLine("Press any key to exit the launcher (game will keep running).");
+            Console.ReadKey(true);
+
+            return 0;
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"Fatal error: {ex.Message}");
+            Console.Error.WriteLine(ex.StackTrace);
+            Console.WriteLine("Press any key to exit.");
+            Console.ReadKey(true);
+            return 1;
+        }
+    }
+}