⚡️(frontend) optimize countdown check in IsIdleDisconnectModal.tsx

Using Array.includes runs in O(n) on every second of the countdown.

Replace the array with a Set to achieve O(1) lookups for better
performance.

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to
 
 - 🔒️(backend) enhance API input validation to strengthen security #1053
 - 🦺(backend) strengthen API validation for recording options #1063
+- ⚡️(frontend) optimize few performance caveats #1073
 
 ### Fixed
 

src/frontend/src/features/rooms/livekit/components/IsIdleDisconnectModal.tsx

@@ -13,7 +13,7 @@ import { useSettingsDialog } from '@/features/settings/hook/useSettingsDialog'
 import { SettingsDialogExtendedKey } from '@/features/settings/type'
 
 const IDLE_DISCONNECT_TIMEOUT_MS = 120000 // 2 minutes
-const COUNTDOWN_ANNOUNCEMENT_SECONDS = [90, 60, 30]
+const COUNTDOWN_ANNOUNCEMENT_SECONDS = new Set([90, 60, 30])
 const FINAL_COUNTDOWN_SECONDS = 10
 
 export const IsIdleDisconnectModal = () => {
@@ -58,7 +58,7 @@ export const IsIdleDisconnectModal = () => {
     if (!connectionObserverSnap.isIdleDisconnectModalOpen) return
 
     const shouldAnnounce =
-      COUNTDOWN_ANNOUNCEMENT_SECONDS.includes(remainingSeconds) ||
+      COUNTDOWN_ANNOUNCEMENT_SECONDS.has(remainingSeconds) ||
       remainingSeconds <= FINAL_COUNTDOWN_SECONDS
 
     if (shouldAnnounce && remainingSeconds !== lastAnnouncementRef.current) {