Fix streak grace period, UNO earnings, hospital UX, wordle/lottery atomicity

- Streak grace now checks LastDeathDate instead of LastActionDate (was
  suppressing streak updates for all active players)
- UNO single-player earnings use net payout (minus wager) not gross
- Hospital sends error message on save failure instead of silent no-op
- Wordle total_earned update moved into stats transaction
- Lottery ticket inserts + community pot add wrapped in single transaction
  with euro refund on failure
- Lottery fixed-tier ticket prize updated with actual prorated amount
- Added last_death_date column to adventure_characters

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/plugin/lottery_draw.go

@@ -148,6 +148,8 @@ func (p *LotteryPlugin) executeDraw(weekStart string) {
 				if amount > 0 {
 					p.euro.Credit(t.UserID, float64(amount), fmt.Sprintf("lottery_%dmatch", tier))
 				}
+				// Update ticket with actual prorated prize (not nominal)
+				lotteryUpdateTicketResult(t.ID, *t.MatchCount, amount)
 			}
 		}
 	}