Add Texas Hold'em arena with classic and short-deck variants

[Muhtasham]

  | Test                            | Status |
  |---------------------------------|--------|
  | Engine Review                   |        |
  | Classic 52-card deck            | ✓      |
  | Short-deck 36-card deck (6-A)   | ✓      |
  | All 10 hand rankings            | ✓      |
  | Classic: Full House > Flush     | ✓      |
  | Short-deck: Flush > Full House  | ✓      |
  | Classic wheel (A-2-3-4-5)       | ✓      |
  | Short-deck wheel (A-6-7-8-9)    | ✓      |
  | Heads-up blind rules            | ✓      |
  | Backward compatibility          | ✓      |
  | End-to-End Games                |        |
  | Classic variant (20 hands)      | ✓      |
  | Short-deck variant (20 hands)   | ✓      |
  | CodeClash Integration           |        |
  | TexasHoldemArena registered     | ✓      |
  | ShortDeckHoldemArena registered | ✓      |
  | Ruff linting                    | ✓      |