export type NormalizedChatType = "direct" | "group" | "channel"; export function normalizeChatType(raw?: string): NormalizedChatType | undefined { const value = raw?.trim().toLowerCase(); if (!value) { return undefined; } if (value === "direct" || value === "dm") { return "direct"; } if (value === "group") { return "group"; } if (value === "channel") { return "channel"; } return undefined; }