chore: import upstream snapshot with attribution

Sources/Services/ContainerAPIService/Client/String+Extensions.swift

@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2026 Apple Inc. and the container project authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Foundation
+
+extension String {
+    public func fromISO8601DateString(to: String) -> String? {
+        if let date = fromISO8601Date() {
+            let dateformatTo = DateFormatter()
+            dateformatTo.dateFormat = to
+            return dateformatTo.string(from: date)
+        }
+        return nil
+    }
+
+    public func fromISO8601Date() -> Date? {
+        let iso8601DateFormatter = ISO8601DateFormatter()
+        iso8601DateFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
+        return iso8601DateFormatter.date(from: self)
+    }
+
+    public func isAbsolutePath() -> Bool {
+        self.starts(with: "/")
+    }
+
+    /// Trim all `char` characters from the left side of the string. Stops when encountering a character that
+    /// doesn't match `char`.
+    mutating public func trimLeft(char: Character) {
+        if self.isEmpty {
+            return
+        }
+        var trimTo = 0
+        for c in self {
+            if char != c {
+                break
+            }
+            trimTo += 1
+        }
+        if trimTo != 0 {
+            let index = self.index(self.startIndex, offsetBy: trimTo)
+            self = String(self[index...])
+        }
+    }
+}