Contract 9.0.0

Participation keeps weekly war-deck facts and drops unreliable daily allocations (Jamie, 2026-09-25).

• clans_participation.members[] keeps war_decks as the total for each recorded war week, with war_points and war_scoring_decks where full verbosity serves them.
• war_decks_by_day, war_battles_by_day and war_days_battled are removed from participation. Sampled game counters and recorded battles cannot reliably allocate a weekly deck total to the game's individual days. war_history remains the exact-week surface for its separately observed attendance facts.