docs: add Related Links section to README

Apple Developer Documentation へのリンクをまとめた "Related Links" セクションを追加。
センサーが依存するフレームワーク・クラスの公式ドキュメントを参照できるようにした。

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: tetujin

README.md

@@ -111,6 +111,11 @@ class Observer:ScreenObserver{
 }
 ```
 
+## Related Links
+
+- [UIScreen | Apple Developer Documentation](https://developer.apple.com/documentation/uikit/uiscreen)
+- [UIApplication | Apple Developer Documentation](https://developer.apple.com/documentation/uikit/uiapplication)
+
 ## Author
 
 Yuuki Nishiyama (The University of Tokyo), nishiyama@csis.u-tokyo.ac.jp
@@ -122,4 +127,3 @@ Copyright (c) 2025 AWARE Mobile Context Instrumentation Middleware/Framework (ht
 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
 
 http://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.
-