feat(rust): Dangerous Treasures — feed, map, Treasure Hunter, Start a Dangerous Treasures event (PLAN_REDESIGNS §14.3.4)

Stage 5 of the §14.3 integration plan, on protocol 14 (docs
rust-link/PROTOCOL.md §20.8).

- dt.started and dt.won are public kinds, dt.ended a staff kind. The new
  dangerousTreasures.js reads each row per viewer: grid and invaderCount for
  everyone, the winner's name for the presence audience (D376), the position,
  the step's key, the winner's Steam id and the invaders for staff.
- Feed lines in the World events filter: "A Dangerous Treasures event has
  started · K12", "Alice won the treasure · K12 · 3 players fought for it".
- Triggers rust.dt.started (with byEvent) and rust.dt.won, public, cooldown
  subject the server, names only.
- eventDangerousTreasures.js: rust.dt.start, "Start a Dangerous Treasures
  event" (risk change, reversible none, budget rust.dt.events), server and
  difficulty. Refused at verify where the server said DT is not loaded or
  console.plugins is false (Rust-Plugins#34). dt-not-ready answers "Dangerous
  Treasures is not ready yet" with retryAfterMs 600000 (D365, D371);
  dt-no-spot retries on core's delay; DT's own refusals are permanent.
- Treasure Hunter (D375): treasuresWon -> treasures_won, the title category
  treasureswon, and a sortable Treasures column shown where the server
  reports DT or a row counts one.
- The map draws a running chest on the world layer; the server settings'
  plugin line names DT and whether a step can start one, from the
  integrations read's new `console`.
- coreApi ^1.15.0, ci/core-ref.json pinned to website main at #215's merge.
  ci/bundle.json ships the two new files; swagger fragment and engagement
  manifest regenerated; README lists DT.

Server 627/627 (16 new in test/dangerousTreasures.test.js) and every check;
client 92/92, build and externals. Booted against the pinned core: 45
triggers, 13 actions, 11 budgets, 21 option sources; 89 routes unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

server/model/events/events.db.js

@@ -151,6 +151,8 @@ const TITLE_SUMS = {
   // Protocol 14 (D356): Safecracker and Scavenger.
   cratesHacked: 'crates_hacked',
   dropsLooted: 'drops_looted',
+  // Protocol 14 (D375): Treasure Hunter.
+  treasuresWon: 'treasures_won',
 }
 
 /** The two *best* fields and their columns: the longest single kill, never a sum. */
@@ -350,6 +352,8 @@ async function leaderboard({ serverId, wipeId = null, sort = 'kills', limit = 25
     // Protocol 14 (D356, D377): the columns Safecracker and Scavenger bring.
     cratesHacked: 'crates_hacked',
     dropsLooted: 'drops_looted',
+    // Protocol 14 (D375): Dangerous Treasures won, Treasure Hunter's column.
+    treasuresWon: 'treasures_won',
   }[sort] || 'kills'
 
   const params = [serverId]
@@ -376,6 +380,7 @@ async function leaderboard({ serverId, wipeId = null, sort = 'kills', limit = 25
             SUM(s.playtime_sec) AS playtimeSec,
             SUM(s.crates_hacked) AS cratesHacked,
             SUM(s.drops_looted) AS dropsLooted,
+            SUM(s.treasures_won) AS treasuresWon,
             MAX(s.balance) AS balance,
             MAX(s.last_seen) AS lastSeen
        FROM ${STATS} s