Poker Deal and Hand-Winner Simulation

Simulate one five-card poker deal. You are given the players in fixed turn order as userIds and all cards in chronological deal order as dealtCards. Card dealtCards[i] is dealt to player userIds[i % userIds.length].
Each card is a two-character code. Its first character is one of 2 through 9, T, J, Q, K, or A. Its second character is one of C, D, H, or S.
After every player has five cards, compare the hands using standard five-card poker order, from strongest to weakest:
straight flush
four of a kind
full house
flush
straight
three of a kind
two pair
one pair
high card
Within a category, compare the deciding ranks from highest to lowest. An ace is normally high, but A-2-3-4-5 is a five-high straight. Suits never break ties.
Return the complete chronological event log:
For each dealt card, append DEAL userId card.
After evaluating all hands, append WINNERS ids, where ids is every tied winner in ascending lexicographic order, joined by commas.

Function
simulatePoker(userIds: String[], dealtCards: String[]) → String[]

Examples
Example 1
userIds = ["alice","bob"]
dealtCards = ["AS","9C","KS","9D","QS","2H","JS","2C","TS","7S"]
return = ["DEAL alice AS","DEAL bob 9C","DEAL alice KS","DEAL bob 9D","DEAL alice QS","DEAL bob 2H","DEAL alice JS","DEAL bob 2C","DEAL alice TS","DEAL bob 7S","WINNERS alice"]
Alice has an ace-high straight flush. Bob has two pair, so Alice is the only winner.
Example 2
userIds = ["a","b"]
dealtCards = ["AS","AH","KD","KC","QH","QS","JC","JD","9S","9C"]
return = ["DEAL a AS","DEAL b AH","DEAL a KD","DEAL b KC","DEAL a QH","DEAL b QS","DEAL a JC","DEAL b JD","DEAL a 9S","DEAL b 9C","WINNERS a,b"]
Both players have the same ace-high hand by rank. Suits do not break ties, so both identifiers are returned.

Constraints
2 <= userIds.length <= 10
Every user identifier is unique and contains only lowercase letters and digits.
dealtCards.length = 5 * userIds.length.
Every card is a valid two-character code, and no card appears more than once.

The trick is turning each hand into a comparable key. Count ranks, then sort rank groups by count descending, then rank descending. That tuple gives your tiebreakers for free: four of a kind, full house, pairs and trips all fall out of the group shape. Put the category number first, then the sorted ranks, and compare tuples directly. Pitfalls: the wheel straight A-2-3-4-5 must be treated as five-high, so the ace counts as 1 there. Straight flush is just flush plus straight. Suits never break ties, so don't include them in the key. Ties must return every winner sorted lexicographically, joined by commas. Deal order uses index mod player count, and the DEAL lines come before WINNERS. If you freeze during the live OA, StealthCoder can supply the hand-evaluator while you check these edge cases.

Memorize the pattern. If you can't, run StealthCoder. The proctor sees the IDE. They don't see what's behind it.