feat(streaming): establish cost budget ledger

Add the validated frame-work profile, deterministic completion charges, and shadow admission meter before enforcing the scheduler in Slice E2. Lifecycle artifacts now expose elapsed work, would-yield limits, backlog bytes/age, and pending owner ledgers without changing accepted execution.

Tests: dotnet build AcDream.slnx -c Release --no-restore; dotnet test AcDream.slnx -c Release --no-build --no-restore (8124 passed, 5 skipped)

tests/AcDream.App.Tests/RuntimeOptionsTests.cs

@@ -1,6 +1,7 @@
 using System.Collections.Generic;
 using AcDream.App;
 using AcDream.App.Rendering.Residency;
+using AcDream.App.Streaming;
 
 namespace AcDream.App.Tests;
 
@@ -20,6 +21,65 @@ public sealed class RuntimeOptionsTests
             _ => null);
 
         Assert.Equal(ResidencyBudgetOptions.Default, options.ResidencyBudgets);
+        Assert.Equal(
+            StreamingWorkBudgetOptions.Default,
+            options.StreamingWorkBudgets);
+    }
+
+    [Fact]
+    public void StreamingWorkBudgetOverridesAreOneTypedProfile()
+    {
+        var values = new Dictionary<string, string?>
+        {
+            ["ACDREAM_STREAM_WORK_MS"] = "1.75",
+            ["ACDREAM_STREAM_WORK_COMPLETIONS"] = "31",
+            ["ACDREAM_STREAM_WORK_CPU_MIB"] = "6",
+            ["ACDREAM_STREAM_WORK_ENTITY_OPS"] = "144",
+            ["ACDREAM_STREAM_WORK_GPU_MIB"] = "5",
+            ["ACDREAM_STREAM_WORK_GL_RETIRE_OPS"] = "23",
+            ["ACDREAM_STREAM_WORK_DEST_RESERVE_PERCENT"] = "60",
+        };
+
+        RuntimeOptions options = RuntimeOptions.Parse(
+            "D:\\dat",
+            name => values.GetValueOrDefault(name));
+
+        Assert.Equal(1.75, options.StreamingWorkBudgets.MaxUpdateMilliseconds);
+        Assert.Equal(31, options.StreamingWorkBudgets.MaxCompletionAdmissions);
+        Assert.Equal(
+            6 * StreamingWorkBudgetOptions.MiB,
+            options.StreamingWorkBudgets.MaxAdoptedCpuBytes);
+        Assert.Equal(144, options.StreamingWorkBudgets.MaxEntityOperations);
+        Assert.Equal(
+            5 * StreamingWorkBudgetOptions.MiB,
+            options.StreamingWorkBudgets.MaxGpuUploadBytes);
+        Assert.Equal(23, options.StreamingWorkBudgets.MaxGlRetireOperations);
+        Assert.Equal(0.60f, options.StreamingWorkBudgets.DestinationReserveFraction);
+    }
+
+    [Theory]
+    [InlineData("0")]
+    [InlineData("-1")]
+    [InlineData("NaN")]
+    [InlineData("Infinity")]
+    [InlineData("bad")]
+    public void InvalidStreamingWorkValuesFallBackIndependently(string value)
+    {
+        RuntimeOptions options = RuntimeOptions.Parse(
+            "D:\\dat",
+            name => name switch
+            {
+                "ACDREAM_STREAM_WORK_MS" => value,
+                "ACDREAM_STREAM_WORK_DEST_RESERVE_PERCENT" => value,
+                _ => null,
+            });
+
+        Assert.Equal(
+            StreamingWorkBudgetOptions.Default.MaxUpdateMilliseconds,
+            options.StreamingWorkBudgets.MaxUpdateMilliseconds);
+        Assert.Equal(
+            StreamingWorkBudgetOptions.Default.DestinationReserveFraction,
+            options.StreamingWorkBudgets.DestinationReserveFraction);
     }
 
     [Fact]