fix(webui): bound startup fetch waits

webui/src/lib/http.ts

@@ -0,0 +1,33 @@
+export const DEFAULT_HTTP_TIMEOUT_MS = 20_000;
+
+export async function fetchWithTimeout(
+  input: RequestInfo | URL,
+  init: RequestInit = {},
+  timeoutMs: number = DEFAULT_HTTP_TIMEOUT_MS,
+): Promise<Response> {
+  if (!Number.isFinite(timeoutMs) || timeoutMs <= 0) {
+    return fetch(input, init);
+  }
+
+  const controller = typeof AbortController !== "undefined"
+    ? new AbortController()
+    : null;
+  let timeoutId: ReturnType<typeof setTimeout> | undefined;
+
+  const request = fetch(input, {
+    ...init,
+    signal: controller?.signal ?? init.signal,
+  });
+  const timeout = new Promise<Response>((_, reject) => {
+    timeoutId = setTimeout(() => {
+      reject(new Error(`Request timed out after ${timeoutMs}ms`));
+      controller?.abort();
+    }, timeoutMs);
+  });
+
+  try {
+    return await Promise.race([request, timeout]);
+  } finally {
+    if (timeoutId !== undefined) clearTimeout(timeoutId);
+  }
+}