Create (and optionally send) an email message

Create a new email message record. Optionally send the email by setting send: true.

Default behavior (send: false or omitted):

• Creates a record in the CRM without sending
• Use this to log emails sent through external systems

Sending emails (send: true):

• Uses team's default provider if emailProviderId is not specified
• Optionally specify emailProviderId to use a specific provider
• Actually sends the email through the specified/default provider
• Provider must be configured and accessible to the API token

Auto-fill behavior:

• If toEmail is blank/omitted, uses the person's primary email (or returns error if none exists)
• If fromEmail is blank/omitted, uses the default email provider's sender email (or returns error if no provider configured)
• This allows simplified message creation when using default contact information