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 A withdrawn style is one `chat-group` retirement, never for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

@@ -32,7 +32,7 @@ permissionsRouter.get(
   '/',
   // #swagger.tags = ['Admin · Rust']
   // #swagger.summary = 'The whole permission model'
-  // #swagger.description = 'Groups with their permissions and members, direct grants, the drift each server reported, the option source of registered permission names, and the sync state of every configured server.'
+  // #swagger.description = 'Groups with their permissions, members and BetterChat style (`chat`, or null), direct grants, the drift each server reported, the option source of registered permission names, and the sync state of every configured server. A drift row of kind `chat-field` is a style field somebody changed in game: `subject` is the group, `object` the field and `detail` what the game holds. `chatFields` lists the twelve BetterChat fields with their types and defaults, for the style editor.'
   /* #swagger.responses[200] = { description: 'The authored model and what each game reported', content: { "application/json": { schema: { $ref: "#/components/schemas/RustPermissionModel" } } } } */
   requireRole('admin'),
   permissions.overview,
@@ -52,7 +52,7 @@ permissionsRouter.put(
   '/groups/:name',
   // #swagger.tags = ['Admin · Rust']
   // #swagger.summary = 'Create or update a permission group'
-  // #swagger.description = 'Writes the group and the permissions it carries in one request, because they are one idea on the form. `scope` is a server id or `*` for the whole fleet. The group is mirrored into each in-scope game as a real group, so third-party plugins that read group membership see it.'
+  // #swagger.description = 'Writes the group and the permissions it carries in one request, because they are one idea on the form. `scope` is a server id or `*` for the whole fleet. The group is mirrored into each in-scope game as a real group, so third-party plugins that read group membership see it. `chat` is the group’s BetterChat style: all twelve fields (`Priority`, `Title`, `TitleColor`, `TitleSize`, `TitleHidden`, `TitleHiddenIfNotPrimary`, `UsernameColor`, `UsernameSize`, `MessageColor`, `MessageSize`, `ChatFormat`, `ConsoleFormat`), each as text; `null` removes the style, which removes the group from BetterChat on the next sync; absent leaves it alone. A format must hold `{Message}` exactly once. A 400 carries one sentence per problem in `errors`.'
   /* #swagger.responses[204] = { description: 'Saved' } */
   /* #swagger.responses[400] = { description: 'Invalid body, or a scope naming no configured server' } */
   requireRole('admin'),
@@ -62,6 +62,9 @@ permissionsRouter.put(
   body('scope').optional().isString().isLength({ min: 1, max: 64 }),
   body('permissions').optional().isArray({ max: 500 }),
   body('permissions.*').isString().matches(NAME),
+  // Shape only; the twelve fields and their rules are `chatStyle.validateStyle`'s,
+  // in the controller, so the form gets one sentence per problem.
+  body('chat').optional({ values: 'null' }).isObject().withMessage('chat is an object of BetterChat fields, or null'),
   validate,
   permissions.putGroup,
 )
@@ -145,7 +148,7 @@ permissionsRouter.post(
   '/drift/:id/adopt',
   // #swagger.tags = ['Admin · Rust']
   // #swagger.summary = 'Adopt a hand edit'
-  // #swagger.description = 'Records a grant or membership somebody made in game as one the site authors, so it stops being reported and starts being maintained. It needs a website account holding that Steam id; without one there is nobody to author it against, and the answer is to revoke it or to ask the player to link.'
+  // #swagger.description = 'Records a grant or membership somebody made in game as one the site authors, so it stops being reported and starts being maintained. It needs a website account holding that Steam id; without one there is nobody to author it against, and the answer is to revoke it or to ask the player to link. For a `chat-field` row it copies the game’s value into the group’s style — which every server in the group’s scope is then pushed — and answers 409 when the group has no style or the value is not one the site accepts.'
   /* #swagger.responses[204] = { description: 'Adopted' } */
   /* #swagger.responses[400] = { description: 'That kind of drift cannot be adopted' } */
   /* #swagger.responses[409] = { description: 'That Steam account is linked to nobody on this site' } */
@@ -159,7 +162,7 @@ permissionsRouter.post(
   '/drift/:id/revoke',
   // #swagger.tags = ['Admin · Rust']
   // #swagger.summary = 'Revoke a hand edit'
-  // #swagger.description = 'Queues the removal rather than performing it: a server that is down keeps the instruction until it comes back. This is the only way the site removes something it did not put there — a sync never does it on its own.'
+  // #swagger.description = 'Queues the removal rather than performing it: a server that is down keeps the instruction until it comes back. This is the only way the site removes something it did not put there — a sync never does it on its own. For a `chat-field` row it puts the site’s value back over the hand edit on the next sync.'
   /* #swagger.responses[202] = { description: 'Queued for the next sync' } */
   /* #swagger.responses[404] = { description: 'No such drift' } */
   requireRole('admin'),