[souffle]

Welcome to the forum.
Your lovely hammy looks to be a long haired mink. In some lights the dark red eyes of these hammies can look black but they are actually red. As they mature they do develop a browny pigment on the ears so it seems she may just now be getting this and as the coat grows in she may also have appeared to change colour.
She does look like quite a young hamster to me and the 'wet tail' may have been due to the stress of moving to a new home and may not have been true wet tail but stress induced diaorrhoea which is nasty but more recoverable that true wet tail. It sounds as if the shop did care for her well but you need to keep a close eye on her as if they simply dosed her up with 'dry tail' the problem may recur. I hope not though.
She is still a baby and as such needs a lot of sleep. She has likely got into a late routine in the quiet of the store. I think maybe 40 minutes is rather too long to have her out and it may be best to try several short sessions rather than one long.
Hammies who have had wet tail can suffer long term after effects depending on how badly damaged the bowel was but the infection. They sometimes do not absorb food well and do not grow as well as normal. They can be prone to recurrence of diarrhoea at the slightest change in food or routine so try and maintain a very even keel with her. I would not change food or use any veggies just now. The diet sounds fine and I would continue with the mix of Hazel and the Mazuri pellets allowing her to eat what she wants.
A useful addition would be a probiotic for small animals such as Avipro or ProC which can be added to water or sprinkled on the food. This will keep her bowel healthy.
Long haired hamsters seem to more susceptable to wet tail for some reason I have heard.
At the first sign of anything amiss make sure you see a vet as early antibiotic treatment can stop the wet tail getting bad.
I think Sunshine or even Sunny is a lovely name and look forward to hearing lots more about her.