Emails deleted/moved from INBOX on server, need also be removed from "contact requests"

[testbird]

To limit and always keep the list of email messages that did not approve for a chat tidy, messages from "contact requests" should automatically get removed when they are moved or deleted on the server INBOX (dealt with by another MUA).

(For chat messages see "Local Chat History" option at https://github.com/deltachat/deltachat-core/wiki/IMAP-strategy #120 #244.)

[r10s]

thanks for the hint, i've added this to #52

[testbird]

Ok, just thought the clean-up would be good for a single-client as well.

[r10s]

for single-client (if delta is the only MUA) this is not needed. if there is any other app with access to the INBOX, this is already multi-client.

[testbird]

Letting any preexisting classic email client count for delta chat mult-client mode may reduce the usability scope a little too much.

Not "downloading deletes" from INBOX introduces an unnecessary bothering chore for deltachat users to delete "bogus contact request". Kind of a put down.
(In addition to the usual email sorting required in classic MUAs, instead of being easy to use.)

Also prevents provider server filters (archiving / deleting emails after a while) to work (no other client involved).

[r10s]

if there is "any preexisting classic email client", we're already talking about multi-client mode.

apart from that, i agree to all points - therefore added this issue to #52 :)

[testbird]

I can't tell which point in #52 is not about chat but about email (contact requests).

[testbird]

Reopen this?
#52 has been marked solved but there are still all old emails under "Emails" (contact requests) long after they were deleted or moved away on the server.

[testbird]

Removing those messages from the email view that got deleted on the server allows deltachat to be used by users that are actually cleaning up their INBOX (either in deltachat or on the server).

An additional (FIFO) displaying limit (500?) might be required for deltachat to work with huge INBOXes that are never cleaned up completely. (New issue?)

[r10s]

i think, we should open a more general issue wrt syncing. it's not only deleted contact requesets

[r10s]

did so: #644