fix: use exact MyMemory matches when top translation is blank

Sources/ConjureKit/MyMemoryAPI.swift

@@ -26,18 +26,35 @@ public enum MyMemoryAPI {
         guard result.quotaFinished != true, result.responseStatus != 429 else {
             throw Failure(message: "MyMemory's anonymous daily quota is exhausted. Try later or choose OpenAI.")
         }
-        guard result.responseStatus == 200,
-              let translation = result.responseData?.translatedText,
-              !translation.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else {
+        guard result.responseStatus == 200 else {
             throw Failure(message: "MyMemory returned no successful translation. Try again later or choose OpenAI.")
         }
-        return translation
+        if let translation = result.responseData?.translatedText,
+           !translation.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
+            return translation
+        }
+        // The service can rank an empty memory first; only use another exact en→ja match.
+        if let match = result.matches?.first(where: {
+            $0.segment == text && $0.source.split(separator: "-").first == "en"
+                && $0.target.split(separator: "-").first == "ja"
+                && !$0.translation.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
+        }) {
+            return match.translation
+        }
+        throw Failure(message: "MyMemory returned no successful translation. Try again later or choose OpenAI.")
     }
 
     private struct Response: Decodable {
         let responseStatus: Int
         let quotaFinished: Bool?
         let responseData: Translation?
+        let matches: [Match]?
+        struct Match: Decodable {
+            let segment: String
+            let translation: String
+            let source: String
+            let target: String
+        }
         struct Translation: Decodable { let translatedText: String? }
     }
     private struct Failure: LocalizedError {