feat(headless): hydrate isolated collision worlds

src/AcDream.Headless/Hosting/HeadlessStaticStateAudit.cs

@@ -0,0 +1,49 @@
+using System.Reflection;
+using AcDream.Core.Physics;
+using AcDream.Headless.Configuration;
+
+namespace AcDream.Headless.Hosting;
+
+/// <summary>
+/// Rejects process-global physics probes whose mutable capture cursors and
+/// last-hit fields cannot be attributed safely when several Runtime roots
+/// share one process. Ordinary diagnostics remain session-labelled through
+/// <see cref="Diagnostics.HeadlessDiagnosticWriter"/>.
+/// </summary>
+internal static class HeadlessStaticStateAudit
+{
+    internal static void ValidateProcessIsolation()
+    {
+        var enabled = new List<string>();
+        foreach (PropertyInfo property in typeof(PhysicsDiagnostics)
+            .GetProperties(BindingFlags.Public | BindingFlags.Static)
+            .OrderBy(static property => property.Name, StringComparer.Ordinal))
+        {
+            if (property.PropertyType != typeof(bool)
+                || property.GetMethod is null
+                || (!property.Name.StartsWith(
+                        "Probe",
+                        StringComparison.Ordinal)
+                    && !property.Name.StartsWith(
+                        "Dump",
+                        StringComparison.Ordinal)))
+            {
+                continue;
+            }
+            if (property.GetValue(null) is true)
+                enabled.Add(property.Name);
+        }
+        if (PhysicsDiagnostics.CollisionShadowSampleEvery > 0)
+            enabled.Add(nameof(PhysicsDiagnostics.CollisionShadowSampleEvery));
+        if (PhysicsResolveCapture.IsEnabled)
+            enabled.Add(nameof(PhysicsResolveCapture));
+
+        if (enabled.Count != 0)
+        {
+            throw new HeadlessConfigurationException(
+                "Multi-session headless mode cannot use process-global "
+                + "physics probes. Disable: "
+                + string.Join(", ", enabled));
+        }
+    }
+}