[HRIS-458]-[BUG-TASK]-Improvement Bug Fix: Initial Error Banner Message in Sign-in url

[EarlJosephClaro]

Issue Link

Backlog: HRIS-458
Test Case: Authentication TCID 19
Slack: Thread

Definition of Done

• The sign-in page no longer triggers an "Email does not exist!" alert when visiting http://localhost:3000/sign-in.

Notes

I fixed the issue where the app incorrectly signed out users and showed the "Email does not exist!" alert on page load. Now, it only triggers signOut() if the API request (SignInMutation) explicitly fails, preventing unnecessary alerts while keeping auto-login working.

Commands to run
1.Run Frontend Client

cd client
npm run dev

2.Run Backend API

cd api
dotnet run

Pre-condition

1. Open localhost:3000/sign-in
2. Sign-in with Sun Asterisk Gmail
3. Logout
4. Refresh Page

Expected Output

• When visiting the sign-in page, users with a valid session should remain logged in without seeing an error.
• If the API confirms the user does not exist, only then should the "Email does not exist!" alert appear, and the user should be signed out.
• If authentication succeeds, the user should be redirected to /my-daily-time-record without unnecessary alerts.

Screenshots/Recordings

Videos:
Before:

https://drive.google.com/open?id=1qxvERylaMR6jwrUFkFSboyjF2QP3AR4c&usp=drive_copy

After:

Testing HRIS Sign-In: Fixing Unexpected 'Email Does Not Exist' Alert

https://drive.google.com/file/d/12Exi1dDbGeEb6EEloXIVY2G2qJNCBiBr/view?usp=sharing