Add Acknowledgments section to README

This update thanks JetBrains for their CLion IDE, highlighting its free availability under an Open Source License. The acknowledgment emphasizes the tool's role in enhancing project development.

README.md

@@ -132,3 +132,9 @@ make test TESTS="-v tests/your_specific_test.phpt"
 Akihito Koriyama
 
 This extension was developed with the assistance of AI pair programming, which helped navigate the complexities of PHP extension development and PECL standards.
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+## Acknowledgments
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+This project was created using [JetBrains CLion](https://www.jetbrains.com/clion/), which is available for free with an [Open Source License](https://www.jetbrains.com/community/opensource/).
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+We'd like to express our gratitude to JetBrains for providing such a powerful and user-friendly development environment.