[#13365] Add validation for email input in feedback form

[nity4jain]

…3365

[#XXXX] Add email regex validation with user hints in feedback form

Fixes #13365 > Add email regex validation with user hints in feedback form

Outline of Solution

• Added regex validation for email input in the feedback form.
• Invalid emails now show red error hints.
• Valid emails now show green confirmation hints.
• Updated the feedback form component logic to prevent invalid emails from being submitted.
• Removed temporary test input and button used for manual testing.

Testing

• Manually verified that invalid emails like plainaddress, @domain.com, [email protected] show red hints.
• Valid emails like [email protected], [email protected] show green hints.

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