Do test it, that will require building krunner and maybe plasma, that can take some time depending on your machine. kde-builder and the LLM can help.
And tell the LLM to keep consistent in code style and do your best to understand the code to spot shortcoming or logical issues. Ask the LLM for review.
It is not fine if reviewing is too hard, too verbose, too hard or convoluted, be mindful of reviewers that are humans, but do mistreat your LLM that’s a program.
And you can learn along the way, LLM can act as teachers.
Very cool of you to try and build it yourself! If I could share an idea: it would be nice if one could also set a timer to an absolute time, for example settings a timer to go off at 18:30, similar to how in the terminal one can do “shutdown 18:30”, which can be very useful instead of having to manually calculate how many minutes it would be until that time.