feat(frontend): Update login and signup feedback

[kcze]

Currently both login and signup page show the same feedback on error on cloud (join the waitlist).

Changes 🏗️

Update login&signup feedback for cloud.

• Use cards for login and signup feedback instead of html list
• Make login page show prompt to redirect user to signup

Checklist 📋

For code changes:

• I have clearly listed my changes in the PR description
• I have made a test plan
• I have tested my changes according to the test plan:
  • Signup&login works with correct credentials
  • Signup&login shows correct error message on wrong credentials
  • Links work correctly

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[deepsource-io]

Here's the code health analysis summary for commits ac8ef9b..222e614. View details on DeepSource ↗.

Analysis Summary

Analyzer	Status	Summary	Link
JavaScript	✅ Success	❗ 1 occurence introduced 🎯 1 occurence resolved	View Check ↗
Python	✅ Success		View Check ↗

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