Start pile with valid first card

[D1Adamm]

As a player, I want the starting card to be randomly selected from the deck according to UNO rules, so that each game begins fairly and unpredictably instead of always starting with the same hardcoded card. This story is complete when the first discard card is drawn from the shuffled deck, only valid number cards can be selected as the starting card, and the starting card is no longer hardcoded in the game logic.

[PrimeAlgorithm]

Total story points: 3