Improve ingame moderation for admins (#3678)

## Description:

Players with the `admin` flare can now kick players from any game
(including public lobbies), not just the lobby creator in private
lobbies.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

w.o.n

src/core/ApiSchemas.ts

@@ -51,6 +51,11 @@ export const TokenPayloadSchema = z.object({
 });
 export type TokenPayload = z.infer<typeof TokenPayloadSchema>;
 
+export const ADMIN_ROLES = ["admin", "root"] as const;
+export function isAdminRole(role: string | null | undefined): boolean {
+  return role === "admin" || role === "root";
+}
+
 export const DiscordUserSchema = z.object({
   id: z.string(),
   avatar: z.string().nullable(),
@@ -72,7 +77,6 @@ export const UserMeResponseSchema = z.object({
   }),
   player: z.object({
     publicId: z.string(),
-    roles: z.string().array().optional(),
     flares: z.string().array().optional(),
     achievements: z.object({
       singleplayerMap: z.array(SingleplayerMapAchievementSchema),