* fix(@cal.com/web): update debounce logic to work correctly and not show non-premium usernames as premium
- removes redundant useMemo hook from UsernameTextfield.tsx & PremiumTextField.tsx
- cancles the debounceAPICall on every unmount of UsernameTextfield.tsx & PremiumTextfield.tsx via useEffect cleanup function
Fixes#15628
* fix(@cal.com/web): update the debounce logic to use the pre-existing useDebounce hook
- update the debounce logic in UsernameTextField.tsx & PremiumTextField.tsx to use the pre-existing useDebounce hook instead of loadsh debounce
- update the debounce delay to 600ms to be consistent with the signup.tsx behavior
Fixes#15628
* fix: signup debounce not working properly
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Co-authored-by: Amit91848 <samit91848@gmail.com>