Fix user discovery search

• Add UDSearchResult model.
• Use UDSearchResult model in UdSearchCallback.
• Workaround: Convert big ints in UdSearchResult JSON to strings.

Sources/XXClient/Models/UDSearchResult.swift

@@ -20,7 +20,8 @@ extension UDSearchResult: Codable {
   }
 
   public static func decode(_ data: Data) throws -> Self {
-    try JSONDecoder().decode(Self.self, from: data)
+    let data = convertBigIntsToStrings(jsonData: data)
+    return try JSONDecoder().decode(Self.self, from: data)
   }
 
   public func encode() throws -> Data {
@@ -30,10 +31,26 @@ extension UDSearchResult: Codable {
 
 extension Array where Element == UDSearchResult {
   public static func decode(_ data: Data) throws -> Self {
-    try JSONDecoder().decode(Self.self, from: data)
+    let data = convertBigIntsToStrings(jsonData: data)
+    return try JSONDecoder().decode(Self.self, from: data)
   }
 
   public func encode() throws -> Data {
     try JSONEncoder().encode(self)
   }
 }
+
+private func convertBigIntsToStrings(jsonData input: Data) -> Data {
+  guard var string = String(data: input, encoding: .utf8) else {
+    return input
+  }
+  string = string.replacingOccurrences(
+    of: #":\s*([0-9]{19,})\s*,"#,
+    with: #": "$1","#,
+    options: [.regularExpression]
+  )
+  guard let output = string.data(using: .utf8) else {
+    return input
+  }
+  return output
+}