fix: recipients with CC role not being editable (#918)

## Description

Fixed issue where setting a recipient role as CC will prevent any
further changes as it is considered as "sent" and "signed".

## Other changes

- Prevent editing document after completed
- Removed CC and Viewers from the field recipient list since they will
never be filled
- Minor UI issues

## Checklist

- [X] I have tested these changes locally and they work as expected.
- [X] I have added/updated tests that prove the effectiveness of these
changes.
- [X] I have followed the project's coding style guidelines.

packages/ui/primitives/document-flow/add-signers.tsx

@@ -105,7 +105,10 @@ export const AddSignersFormPartial = ({
     }
 
     return recipients.some(
-      (recipient) => recipient.id === id && recipient.sendStatus === SendStatus.SENT,
+      (recipient) =>
+        recipient.id === id &&
+        recipient.sendStatus === SendStatus.SENT &&
+        recipient.role !== RecipientRole.CC,
     );
   };