perf(api,frontend): index hot queries, paginate chats, fix realtime

frontend/src/lib/api/endpoints.ts

@@ -99,10 +99,19 @@ export function logoutAccount(accountId: number): Promise<void> {
   return request<void>(`/accounts/${accountId}`, { method: "DELETE" });
 }
 
-export function listChats(page: Page = {}): Promise<Chat[]> {
+interface ChatPage extends Page {
+  folder_id?: number;
+  search?: string;
+}
+
+export function listChats(page: ChatPage = {}): Promise<Chat[]> {
   return request<Chat[]>("/chats", { account: true, query: { ...page } });
 }
 
+export function getChat(chatId: number): Promise<Chat | null> {
+  return request<Chat | null>(`/chats/${chatId}`, { account: true });
+}
+
 export function listFolders(): Promise<Folder[]> {
   return request<Folder[]>("/folders", { account: true });
 }