Track unable to become ready within timeout

Summary: This is currently done by querying the 'console-log' event. Instead, make it type safe and official.

Reviewed By: antonk52

Differential Revision: D50927954

fbshipit-source-id: ff767acdc51b942c6deb92ffbfd93288b3367062

desktop/flipper-server-core/src/server/startServer.tsx

@@ -110,6 +110,7 @@ export async function startServer(
 }> {
   setTimeout(() => {
     if (!isReady && isProduction()) {
+      tracker.track('server-ready-timeout', {timeout: timeoutSeconds});
       console.error(
         `[flipper-server] Unable to become ready within ${timeoutSeconds} seconds, exit`,
       );

desktop/flipper-server-core/src/tracker.tsx

@@ -49,6 +49,7 @@ type TrackerEvents = {
   'server-socket-already-in-use': {};
   'server-open-ui': {browser: boolean; hasToken: boolean};
   'server-ws-server-error': {port: number; error: string};
+  'server-ready-timeout': {timeout: number};
   'browser-connection-created': {
     successful: boolean;
     timeMS: number;