Contract 6.28.0

The ranking tools, after the Elixir Gym's first run on them (feedback #136-#138).

• rankings_clan_ladder says when places on the page share a score: the game lists a tie in its own order, so rank inside it, and rank against previous_rank, is not a standing (#136). The global clan board had 360 clans tied at the 140,000 ceiling, ranked 1 to 360.
• Mode boards stop carrying the Path of Legends notes, and say that their rating is the event's own. snapshot.standings_changed_at on a mode board, and on each row of the location: "list" catalog, says when rank or rating last moved. A snapshot is also written when only a clan changes, so a closed event's observed_at read as today. A note says when a board's standings have not moved in two days (#137).
• The notes that point at per-battle rank and rating name the fields battles_query serves: global_rank, starting_trophies, trophy_change (#138).
• players_profile points lifetime donations at the players_timeline total_donations series; the note named a lifetime field the profile never carried.

Additive fields and notes; no value changes.