CiviCase - Send a Copy of Activity action should be logged in the case

Currently there is no record of the fact that the user "Sent a Copy" of an activity to someone else. This action should be recorded for audit purposes.

Implementation
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For each recipient of "Send a Copy":

• insert an activity and case_activity record with recipient as activity target (this is the same logic as we use when sending an email to a Case Role from CaseView page)

Use the following values for the activity record:

• Activity Type = "Email"

• source_record_id = ID of the activity being "copied" (using the revision of the activity after saving - which I believe matches the data being sent in the email copy)

• Subject = "{$originalActivitySubject} - copy sent to {$recipientSortName}"

• Details = $bodyOfActualEmailSent (this will be text email formatted activity data)

• Status = Completed

• Actual Date = now()

• Medium = Email

• is Auto = false

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