test : Add and maintain 100% unit test coverage for RequireAuth.tsx

Issue Summary

Added comprehensive unit tests for RequireAuth.tsx and achieved 100% test coverage.

Current behavior:

• RequireAuth.tsx handles three authentication guard states:
  • shows a loading message while auth state is not ready
  • redirects unauthenticated users to /login
  • renders protected children for authenticated users

What was done:

• wrote unit tests covering all auth guard branches
• verified loading-state rendering
• verified redirect behavior for unauthenticated users
• verified protected content rendering for authenticated users
• confirmed redirect preserves the current location in navigation state

Result:

• RequireAuth.tsx now has 100% statement, branch, function, and line coverage
• route protection behavior is fully validated and regression-safe