If you plan to maintain the application in the future, using MVC/MVP/MVVM patterns will reduce the cognitive load, allowing you to implement new features and fix bugs much faster. I also noticed that you started writing this small application from May 10 to September 13 (with 'First Production' commits on September 7), which is almost 4 months. However, such an application can usually be written within 1 month at most (with design patterns), even if the developer is a beginner. The further the application develops, the harder it will be to maintain, because too much refactoring will be required (large chunks of code will need to be deleted or replaced, which increases the risk of new bugs). In addition, inheritance is necessary so that, through polymorphism, implementations can be replaced without introducing new bugs and while extending functionality. In short, there needs to be a balance between inheritance and refactoring so that the application can be maintained for decades.
If you add an AGENTS.md, the AI agent will work more efficiently, and there will be far fewer problems like the ones you’re facing. You can include sections such as Security, coding style guidelines, writing unit tests, etc.
All the logic and UI code of your application is in a single file, MainActivity.kt (not counting the app theme, those files are separate), which has 1073 lines of code. No services, repositories, models, utility files, and no design patterns to make your life easier. Conclusion: maintaining the project will be very, very difficult. I’m impressed by your iron nerves.
Tags in Git are useful when you need to make a release, upload files to that release, and provide a download link for the file. That’s when I personally use tags.