refactor: implements a custom date decoding strategy

Sources/OllamaKit/Extensions/JSONDecoder+Default.swift

@@ -9,14 +9,27 @@ import Foundation
 
 internal extension JSONDecoder {
     static var `default`: JSONDecoder {
-        let dateFormatter = DateFormatter()
-        dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSSSSSSSZZZZZ"
-        dateFormatter.locale = Locale(identifier: "en_US_POSIX")
-        dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
-
         let decoder = JSONDecoder()
-        decoder.dateDecodingStrategy = .formatted(dateFormatter)
         decoder.keyDecodingStrategy = .convertFromSnakeCase
+        decoder.dateDecodingStrategy = .custom { decoder -> Date in
+            let container = try decoder.singleValueContainer()
+            let dateString = try container.decode(String.self)
+
+            let formatter = ISO8601DateFormatter()
+            formatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
+
+            if let date = formatter.date(from: dateString) {
+                return date
+            }
+
+            formatter.formatOptions = [.withInternetDateTime]
+
+            if let date = formatter.date(from: dateString) {
+                return date
+            }
+
+            throw DecodingError.dataCorruptedError(in: container, debugDescription: "Cannot decode date string \(dateString)")
+        }
 
         return decoder
     }