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 A withdrawn style is one `chat-group` retirement, never for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/admin/visibility.router.js

@@ -37,7 +37,7 @@ visibilityRouter.put(
   '/',
   // #swagger.tags = ['Admin · Rust']
   // #swagger.summary = 'Change who may see who is online, who may see a clan roster, or which servers say news in chat'
-  // #swagger.description = 'Sets the presence fleet default, one or more server overrides, the clan roster audience, the per-server news-in-chat switches, or any of them together. A server set to `null` follows the fleet default again. `news` maps a server id to `true` or `false`: whether a published news post is also said in the in-game chat of that server (off by default). Validated whole before anything is written: a request naming a server that does not exist changes nothing. Widening the clan roster audience also shows which members are online to that audience, because a roster row carries it. `map` is `{ fleet, servers }`: `fleet` maps a layer (`world`, `events`, `players`, `bases`) to an audience and `mates` to true or false; `servers` maps a server id to the same shape, where null follows the fleet. The players layer never shows more than who may see who is online, whatever it is set to.'
+  // #swagger.description = 'Sets the presence fleet default, one or more server overrides, the clan roster audience, the per-server news-in-chat switches, or any of them together. A server set to `null` follows the fleet default again. `news` maps a server id to `true` or `false`: whether a published news post is also said in the in-game chat of that server (off by default). `newsDelivery` maps a server id to `chat` or `popup`: where that post goes — a popup needs PopupNotifications on the server, and one without it refuses the post with a reason. Validated whole before anything is written: a request naming a server that does not exist changes nothing. Widening the clan roster audience also shows which members are online to that audience, because a roster row carries it. `map` is `{ fleet, servers }`: `fleet` maps a layer (`world`, `events`, `players`, `bases`) to an audience and `mates` to true or false; `servers` maps a server id to the same shape, where null follows the fleet. The players layer never shows more than who may see who is online, whatever it is set to.'
   /* #swagger.requestBody = { required: true, content: { "application/json": { schema: { $ref: "#/components/schemas/RustVisibilityUpdate" } } } } */
   /* #swagger.responses[200] = { description: 'Saved; answers the new state', content: { "application/json": { schema: { $ref: "#/components/schemas/RustVisibility" } } } } */
   /* #swagger.responses[400] = { description: 'An audience that does not exist' } */
@@ -47,6 +47,7 @@ visibilityRouter.put(
   body('servers').optional().isObject().withMessage('servers maps a server id to an audience or null'),
   body('clanRoster').optional().isIn(CLAN_AUDIENCES).withMessage(`clanRoster must be one of ${CLAN_AUDIENCES.join(', ')}`),
   body('news').optional().isObject().withMessage('news maps a server id to true or false'),
+  body('newsDelivery').optional().isObject().withMessage('newsDelivery maps a server id to chat or popup'),
   body('map').optional().isObject().withMessage('map carries fleet and servers, each an object of layer switches'),
   validate,
   visibility.update,