[testing] duplicate invitation

[cch5ng]

• cleanup duplicate invitation definition

• set init id on message on the client side (needed in order to update the message with appropriate translation)

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(update) the reason why this matters is because if there are duplicate approved invitations in the database, this could cause inconsistencies in saving and retrieving conversations

revisit testing for duplicate invitation logic

while testing the updated validation error display on invitation dialog, I felt like some invitations were sent to existing contacts. so maybe the definition of duplicate needs to be expanded

[cch5ng]

put on hold; was working on testing for case: send invite to registered and non registered users (test dupe invitation)

already tested case (send invite to only registered users)