Conversation in mail list

[bedhub]

As a user I want to see a clear list of ongoing conversations in the list so that I don't have to scan through multiple mails that belong to the same conversation.

AC

• There is a filter option to filter mail list by conversation.
• When filter is active only the newest email of a conversation is shown in the list
• The visible list entry shows the amount of emails that were filtered out
• Selecting the entryshows the whole conversation and  opens the latest email in the viewer
• Toolbar actions:
  • Reply/Reply all/Forward will do the action for the newest email
  • Move/Delete: Move all emails from the folder to its new destination (so it doesn't appear in the inbox anymore).
  • Mark read/unread: Applies to all  emails within that folder.

Notes

Still some questions need to be answered before starting with this issue https://github.com/tutao/tutanota/issues/5052

[MasterInQuestion]

    This may be implemented through allowing selected folders to be tagged as the information source of specific Conversation.