Add Hermes Agent package fallback and xAI OAuth (#808)

packages/client/src/api/hermes/xai-auth.ts

@@ -0,0 +1,29 @@
+import { request } from '../client'
+
+export interface XaiStartResult {
+  session_id: string
+  authorization_url: string
+  expires_in: number
+}
+
+export interface XaiPollResult {
+  status: 'pending' | 'approved' | 'expired' | 'error'
+  error: string | null
+}
+
+export interface XaiStatusResult {
+  authenticated: boolean
+  last_refresh?: string
+}
+
+export async function startXaiLogin(): Promise<XaiStartResult> {
+  return request<XaiStartResult>('/api/hermes/auth/xai/start', { method: 'POST' })
+}
+
+export async function pollXaiLogin(sessionId: string): Promise<XaiPollResult> {
+  return request<XaiPollResult>(`/api/hermes/auth/xai/poll/${sessionId}`)
+}
+
+export async function getXaiAuthStatus(): Promise<XaiStatusResult> {
+  return request<XaiStatusResult>('/api/hermes/auth/xai/status')
+}