Ultimately, I implemented the AHS-XY-Wing/AHS-W-Wing algorithm and extended the definition of RCC.
The app has also added theme modes; you can switch to the dark theme for late-night use.
You can experience these updates at the following URL:
https://yzf-sudoku.github.io/yzf-sudoku-web/Please explore additional features on your own; the program includes a detailed user manual and a quick-start guide.
Please feel free to submit suggestions for improvement and bug reports.