improve: add automatic token refresh functionality

Overview

This PR implements automatic token refresh functionality to improve user experience by eliminating unnecessary re-authentication when access tokens expire.

Changes

• Added refresh token validation check before attempting refresh
• Implemented automatic token refresh using refresh_token_request when access tokens are expired but refresh tokens are still valid
• Maintains user session continuity without interrupting user workflow
• I split it into functions because I got an error with lint.

Behavior

Before: Users were forced to re-authenticate every time their access token expired, even when refresh tokens were still valid.

After: The system automatically attempts to refresh expired access tokens using valid refresh tokens, only requiring re-authentication when refresh tokens are also invalid or refresh fails.

Testing

• Tested with expired access token and valid refresh token
• Tested with invalid refresh token scenario
• Confirmed local storage cleanup on failures