refactor(server): drop the state helpers the injected stores replaced

setPermissionsCache and the free leaveRoom, leaveAllRooms and
leaveAllBooks lost their last caller when the services moved onto the
injected stores.

server/src/nest/permissions/permissions-cache.ts

@@ -59,11 +59,6 @@ export function getPermissionsCache(): Promise<Map<string, PermissionLevel> | nu
   return permissionsCacheSlot.get().get();
 }
 
-/** Install a fresh cache map and return it (the loader fills it in place). */
-export function setPermissionsCache(next: Map<string, PermissionLevel>): Promise<Map<string, PermissionLevel>> {
-  return permissionsCacheSlot.get().set(next);
-}
-
 export function invalidatePermissionsCache(): Promise<void> {
   return permissionsCacheSlot.get().invalidate();
 }

server/src/nest/realtime/ws-state.ts

@@ -174,14 +174,6 @@ export function joinRoom(ws: TrekWebSocket, tripId: number): void {
   roomsSlot.get().join(ws, tripId);
 }
 
-export function leaveRoom(ws: TrekWebSocket, tripId: number): void {
-  roomsSlot.get().leave(ws, tripId);
-}
-
-export function leaveAllRooms(ws: TrekWebSocket): void {
-  roomsSlot.get().leaveAll(ws);
-}
-
 // ── Studio books ──────────────────────────────────────────────────────────
 
 export interface BookPeer {
@@ -199,11 +191,6 @@ export function leaveBook(ws: TrekWebSocket, journeyId: number): void {
   roomsSlot.get().leaveBook(ws, journeyId);
 }
 
-/** Every book this socket had open — called when the connection goes. */
-export function leaveAllBooks(ws: TrekWebSocket): number[] {
-  return roomsSlot.get().leaveAllBooks(ws);
-}
-
 /**
  * Who is in a book, by socket rather than by user.
  *