fix(control-ui): measure and decouple slow refreshes

Add Control UI timing attribution for tab visibility, refresh phases, secondary refresh groups, and gateway RPCs. Decouple slow Overview, Cron, and Nodes secondary refreshes from primary tab feedback, and report Cron runs timing from the controller's real ok/error/skipped load outcome.

Also keeps telemetry secret-safe by excluding request params and response bodies, adds focused regression coverage for RPC attribution and stale/failed background refreshes, and carries the latest-main Discord test fixture correction needed for check:test-types.

Fixes #64004.

extensions/discord/src/monitor/message-handler.preflight-channel-context.test.ts

@@ -9,7 +9,7 @@ describe("resolveDiscordPreflightChannelContext", () => {
       channelName: "\uC2E4\uD5D8",
       guildName: "Guild",
       guildInfo: null,
-      threadChannel: undefined,
+      threadChannel: null,
     });
 
     expect(context.configChannelSlug).toBe("");