Remove packaged runtime repository dependency

engine/Age.Engine.Tests/OpcodeTableTests.cs

@@ -4,6 +4,21 @@ using Xunit;
 
 public class OpcodeTableTests
 {
+    [Fact]
+    public void LoadsFromCallerOwnedStreamWithoutClosingIt()
+    {
+        using var source = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(
+            """
+            {"opcodes":[{"op":"0x55","label":"mov","argc":2}]}
+            """));
+
+        OpcodeTable table = OpcodeTableJson.Load(source);
+
+        Assert.True(source.CanRead);
+        Assert.Equal("mov", table.Label(0x55));
+        Assert.Equal(2, table.Argc(0x55));
+    }
+
     [Fact]
     public void LoadsCompleteAgeCatalog()
     {

engine/Age.Engine/Sys4/OpcodeTableJson.cs

@@ -5,7 +5,14 @@ public static class OpcodeTableJson
 {
     public static OpcodeTable Load(string path)
     {
-        using var doc = JsonDocument.Parse(File.ReadAllText(path));
+        using FileStream stream = File.OpenRead(path);
+        return Load(stream);
+    }
+
+    public static OpcodeTable Load(Stream stream)
+    {
+        ArgumentNullException.ThrowIfNull(stream);
+        using var doc = JsonDocument.Parse(stream);
         var dict = new Dictionary<int, (string, int)>();
         foreach (var e in doc.RootElement.GetProperty("opcodes").EnumerateArray())
         {