Flour is many years expired but still looks good

Tea bags will be fine for at least a year in the pantry, but even long after that, they're still safe to consume. They just might change colour or flavour.

If your tea has an expiration date then it's just for best quality, not safety. I've personally found tea bags sitting at the back of the pantry that were more than 3 years old, the packaging had even started to fade, and the tea was still fine. I just had to steep it for a little longer.

I've never made Citrus Sugar, but I certainly have made vanilla sugar. Crystaline sugar soaks up the moisture, so if bacteria or mold were to invade the pot, it would be dehydrated quickly and wouldn't survive, let alone thrive. They need a good bit of moisture to reproduce. I've never had a problem with my vanilla sugar and it doesn't take long for the vanilla beans to turn into little vanilla toothpicks.