Worms can affect the overall health of the bird. But it sounds like she's happy and well within herself. This is why I suggested getting a fecal float to see if worms were even an issue.
When she stopped laying, did she molt? Grow new feathers?
Check her over for lice/mites, see that her crop is emptying, just so you've covered some of the basics.
It can be hard to know why a hen isn't laying eggs. Each one is an individual, even within the same breed. Some take a break for a long while and resume laying like gangbusters. Others may lay for a period of time and never lay again, but live for years.
