Feat: Check email validity at client level

[SirrorsMoore1975]

Current version has email check for email validity at the backend server level, but it won't show whether the email used is not excepted on the frontend. The frontend also needed to check validity of an email if they have domain and dot

• show warning message below the email input box while submit review to warn user at the email section when:
• the email typed in is not a valid email
• the email typed has already been used
• the email typed exceeded the limit (255) (Are you sure your email input here are valid?)

Partially superceding with #71