fix(download): include required root-level files without a metadata extension

Sources/FluidAudio/Shared/Download/ModelHub.swift

@@ -770,7 +770,9 @@ public enum ModelHub {
                     itemPath.hasSuffix(".json") || itemPath.hasSuffix(".model") || itemPath.hasSuffix(".bin")
                 return isInSubPath && (matchesPattern || isMetadata)
             }
-            return patterns.isEmpty || patterns.contains { itemPath.hasPrefix($0) }
+            // Patterns carry a trailing "/" (bundle directories); a required root-level
+            // *file* (e.g. `tokenizer.model`) matches when the pattern is exactly its path.
+            return patterns.isEmpty || patterns.contains { itemPath.hasPrefix($0) || $0 == itemPath + "/" }
                 || itemPath.hasSuffix(".json") || itemPath.hasSuffix(".txt")
         }
     }

Tests/FluidAudioTests/Shared/ModelHubIncludeRuleTests.swift

@@ -133,4 +133,19 @@ final class ModelHubIncludeRuleTests: XCTestCase {
         XCTAssertTrue(rule("vocab.txt", false))
         XCTAssertFalse(rule("Other.mlmodelc/model.mil", false))
     }
+
+    // MARK: - Root-level repo with a required non-JSON file
+
+    func testRequiredRootFileWithoutMetadataExtensionIncluded() {
+        // `tokenizer.model` is a required file at the repo root. Patterns carry a
+        // trailing "/", so a prefix match alone never admitted it and the verify
+        // pass threw `modelNotFound`.
+        let include = ModelHub.repoIncludeRule(
+            subPath: nil, patterns: ["Frame.mlmodelc/", "config.json/", "tokenizer.model/"])
+        XCTAssertTrue(include("tokenizer.model", false))
+        XCTAssertTrue(include("config.json", false))
+        XCTAssertTrue(include("Frame.mlmodelc/model.mil", false))
+        XCTAssertFalse(include("tokenizer_test_vectors.model", false))
+        XCTAssertFalse(include("Encoder.mlmodelc/model.mil", false))
+    }
 }