do not let the frontend send exponents instead of ints. cap it at 1 billion

[Alex Cohen]

INFO:	[10][2023-12-10 13:08:38,576] [main]  /api/wow/shoppinglist params: {"region": "EU", "itemID": 22277, "maxPurchasePrice": 2e+21, "connectedRealmIDs": {}}
ERROR:	[11][2023-12-10 13:09:23,802] [main]  Handling APITypeException: [{'name': 'maxPurchasePrice', 'type_error': "<class 'NoneType'>", 'expected': "<class 'int'>", 'payload': '{"region": "EU", "itemID": 22277, "maxPurchasePrice": null, "connectedRealmIDs": {}}'}]

So that is bad and causes errors we need to make it so the frontend doesnt try to do this. Dont let anyone send an int over 1 billion.