[Components] mailboxlayer

# mailboxlayer
## URLs
- https://mailboxlayer.com/documentation
## Webhook Sources
### new-error-alert-instant
#### Description
Emit new event instantly when an error occurs in processing an email validation request. Requires configuring a webhook URL in the app's interface.
## Polling Sources
### new-email-validation-request
#### Description
Emit new event when a new email validation request is logged in the system. You can configure the interval to check for these requests.
## Actions
### validate-email
#### Description
Validate a given email address. Requires the email address as input. Optionally, provide validation rules or filters.
### get-email-validation-status
#### Description
Retrieve the status and details of a specific email validation request. Requires the request ID as input.
### verify-smtp-server
#### Description
Check and verify the SMTP server associated with an email domain. Requires an email address or domain as input.

Start with the repository's existing API components and compare their structure with the mailboxlayer documentation at https://mailboxlayer.com/documentation. Implement the listed webhook source, polling source, and three email-validation actions, then verify that the component exposes the stated inputs and outputs.

Written by the indexing model from the issue text.