fix: 前端时钟校准问题

frontend/src/lib/api.ts

@@ -20,6 +20,19 @@ export function fetchVideoStatus() {
   return fetchJson<VideoStatus>('/api/video/status/')
 }
 
+export async function fetchClockCalibrationSample() {
+  const response = await fetch(`${API_BASE}/api/clock/calibrate/`, {
+    cache: 'no-store',
+  })
+  if (!response.ok) {
+    throw new Error(`clock calibration failed: ${response.status} ${response.statusText}`)
+  }
+  return response.json() as Promise<{
+    server_received_unix_ms: number
+    server_sent_unix_ms: number
+  }>
+}
+
 export function buildVideoFrameUrl(frameKey: number) {
   return `${API_BASE}/api/video/frame/?frame=${frameKey}&t=${Date.now()}`
 }