Making it easier to figure out how to create an AppImage

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I saw that there are various tools that make it simpler to create an AppImage. I struggled with errors like execv error: No such file or directory when trying to create an AppImage for a Flutter application on Linux, while following tutorials like this.
Moreover, even on seeing the AppImage developer tools portion of this repository, I didn't initially understand what those tools were for (because I'm new to all this). I eventually prompted Grok and it created this program for me which worked well.

Improvements that could be done:

1. The Readme file of this repository could incorporate screenshots and slightly longer explanations about each of the tools so that anyone new to it would understand what it is and be able to use it.
2. Instead of having various separate tools, it might help to create a single Python application which invokes the necessary tools and does the necessary downloads automatically based on the User's executables, to build an AppImage without needing much User intervention.
3. Better SEO-optimised tutorials on the internet could lead people to the right location to figure out how to create AppImages.
4. Some things could be simplified. For example, the default directory for specifying an icon in the .desktop file is some long sequence of subfolders. If an icon is icon.png, then it has to be mentioned as icon in the .desktop file. Such things can be made much simpler, instead of requiring the User to have to refer various tutorials and manuals to figure it out.