Fix: propagate autoentity resolution counts to child configs during validation

When using `data-source-files`, the metadata provider stores autoentity
resolution counts only on the root (merged) config. ValidateRootConfig
now copies those counts to each child config before per-child validation,
so child configs with only autoentities correctly pass the entity-presence
check instead of failing with "No entities found".

Adds two regression tests:
- TestChildWithDataSourceAndAutoentitiesResolvingEntitiesIsValid
- TestRootAndChildBothWithAutoentitiesResolvingEntitiesIsValid

Author: Copilot

src/Cli.Tests/ValidateConfigTests.cs

@@ -883,6 +883,72 @@ public void TestChildWithEntitiesAndAutoentitiesResolvingZeroLogsNamedWarning()
         VerifyAutoentityZeroDiscoveredWarning(loggerMock, expectedFileNameInMessage: "child-db.json");
     }
 
+    /// <summary>
+    /// Child config with only autoentities that resolve to >0 entities is valid.
+    /// Simulates the production code path where the metadata provider stores resolution
+    /// counts on the root (merged) config rather than on the child config directly.
+    /// This is the regression test for the bug where child-config autoentities caused
+    /// "No entities found" even when they were expanded successfully.
+    /// Covers child truth-table row C5 (DS=1, E=0, AE=1, resolved>0, counts on root).
+    /// </summary>
+    [TestMethod]
+    public void TestChildWithDataSourceAndAutoentitiesResolvingEntitiesIsValid()
+    {
+        // Child has no explicit entities; only autoentities.
+        RuntimeConfig childConfig = BuildTestConfig(
+            hasDataSource: true,
+            entities: new(),
+            autoentities: new() { { "ae1", BuildSimpleAutoentity() } });
+        childConfig.IsChildConfig = true;
+
+        RuntimeConfig rootConfig = BuildTestConfig(
+            hasDataSource: false, entities: new(),
+            dataSourceFiles: new DataSourceFiles(new[] { "child-db.json" }));
+        rootConfig.ChildConfigs.Add(("child-db.json", childConfig));
+
+        // Simulate production: metadata provider stores counts in the root config,
+        // NOT directly on the child config.
+        rootConfig.AutoentityResolutionCounts["ae1"] = 3;
+
+        RuntimeConfigValidator validator = BuildValidator(rootConfig);
+        validator.ValidateDataSourceAndEntityPresence(rootConfig);
+
+        Assert.AreEqual(0, validator.ConfigValidationExceptions.Count,
+            "Child config with autoentities that resolved entities should pass validation.");
+    }
+
+    /// <summary>
+    /// Both root and child configs have autoentities that resolve to >0 entities.
+    /// Resolution counts for both are stored only on the root config (as the metadata
+    /// provider does at runtime). Validation must pass for both configs.
+    /// </summary>
+    [TestMethod]
+    public void TestRootAndChildBothWithAutoentitiesResolvingEntitiesIsValid()
+    {
+        RuntimeConfig childConfig = BuildTestConfig(
+            hasDataSource: true,
+            entities: new(),
+            autoentities: new() { { "child-ae", BuildSimpleAutoentity() } });
+        childConfig.IsChildConfig = true;
+
+        RuntimeConfig rootConfig = BuildTestConfig(
+            hasDataSource: true,
+            entities: new(),
+            dataSourceFiles: new DataSourceFiles(new[] { "child-db.json" }),
+            autoentities: new() { { "root-ae", BuildSimpleAutoentity() } });
+        rootConfig.ChildConfigs.Add(("child-db.json", childConfig));
+
+        // Simulate production: metadata provider stores ALL counts in the root config.
+        rootConfig.AutoentityResolutionCounts["root-ae"] = 2;
+        rootConfig.AutoentityResolutionCounts["child-ae"] = 4;
+
+        RuntimeConfigValidator validator = BuildValidator(rootConfig);
+        validator.ValidateDataSourceAndEntityPresence(rootConfig);
+
+        Assert.AreEqual(0, validator.ConfigValidationExceptions.Count,
+            "Root and child configs both with autoentities that resolved entities should pass validation.");
+    }
+
     /// <summary>
     /// Helper: verifies that the autoentity-discovered-zero warning was logged at least once,
     /// optionally also checking that the formatted message contains a child config file name.

src/Core/Configurations/RuntimeConfigValidator.cs

@@ -739,6 +739,18 @@ private void ValidateRootConfig(RuntimeConfig runtimeConfig)
         // Validate each child config independently.
         foreach ((string fileName, RuntimeConfig childConfig) in runtimeConfig.ChildConfigs)
         {
+            // The metadata provider stores autoentity resolution counts on the root (merged)
+            // config. Copy those counts to the child config so per-child validation can find
+            // them. Only copy if the child hasn't already been populated (e.g. in unit tests).
+            foreach (KeyValuePair<string, Autoentity> ae in childConfig.Autoentities)
+            {
+                if (!childConfig.AutoentityResolutionCounts.ContainsKey(ae.Key)
+                    && runtimeConfig.AutoentityResolutionCounts.TryGetValue(ae.Key, out int count))
+                {
+                    childConfig.AutoentityResolutionCounts[ae.Key] = count;
+                }
+            }
+
             ValidateNonRootConfig(childConfig, configName: fileName);
         }
     }