feat(rust): chat titles, BetterChat group styles, the voice and popups (phase 17)

PLAN.md §33, D134-D143. Protocol 12.

- Chat titles (D135-D137): per-server rules (stat, top N, text, colour)
  that rank the current wipe, and a mode (first | all | up to N). Worked
  out once in model/titles and read three ways: pushed whole to the game by
  a new titleSync loop (on change, restart or wipe), and on every
  leaderboard row as `titles`. Admin: PUT /servers/:id/titles.
- Group styles (D138, D139): a site group may carry all twelve BetterChat
  fields (rust_perm_group_chat). They ride perm.sync with `expect` from the
  pushed ledger, which gains a value column; a field changed in game is a
  `chat-field` drift row with the game's value, adopted into the style or
  put back. A withdrawn style is one `chat-group` retirement, never for
  `default`, cleared from the ledger only once BetterChat removed it.
- The voice (D140): one fleet setting naming a styled group; news and
  rust.announce chat lines carry its format and the plugin says them with
  no sender. Admin: GET/PUT /voice.
- Popups (D141, D142): rust.announce gains `delivery` (still version 1,
  from rust.options.delivery); each server gains news_delivery beside the
  news switch; `popup-unavailable` is not retried.
- GET /servers/:id/integrations reads, live, which optional mods a server
  has loaded. README lists BetterChat and PopupNotifications as optional.

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

server/router/public/rust.router.js

@@ -82,7 +82,7 @@ rustRouter.get(
   '/servers/:id/leaderboard',
   // #swagger.tags = ['Public · Rust']
   // #swagger.summary = 'The leaderboard for one Rust server'
-  // #swagger.description = 'Per-wipe when `wipe` is given, all-time otherwise. All-time is the per-wipe rows summed rather than a second set of counters, so a wipe splits a player’s history without ending it. `lastSeen` is withheld below the operator’s presence audience: a gather tally refreshes it every minute a player is on, so it would name who is online.'
+  // #swagger.description = 'Per-wipe when `wipe` is given, all-time otherwise. All-time is the per-wipe rows summed rather than a second set of counters, so a wipe splits a player’s history without ending it. `lastSeen` is withheld below the operator’s presence audience: a gather tally refreshes it every minute a player is on, so it would name who is online. Each row carries `titles`: the chat titles that player holds now, as `[{ text, color }]` in the order the game shows them, and an empty list for a player with none. Titles rank the CURRENT wipe whichever wipe the page asks for, and are set by the operator’s rules.'
   // #swagger.parameters['id'] = { in: 'path', required: true, description: 'The server’s slug', schema: { type: 'string' } }
   // #swagger.parameters['wipe'] = { in: 'query', required: false, description: 'Restrict to one wipe id', schema: { type: 'string' } }
   // #swagger.parameters['sort'] = { in: 'query', required: false, description: 'kills, deaths, npcKills or playtime', schema: { type: 'string' } }