fix: Look up ContactId::DEVICE by ContactId::DEVICE_ADDR (#6323)

At least this fixes the bug when the device chat is e.g. archived by the user on one device, but
this user action is synchronized as archiving a chat with a new contact having the address
"device@localhost" on another device. Not sure if we want to sinchronize actions on the device chats
at all because they are chats with different devices, but maybe that simplifies UX, so let's discuss
it first and maybe disable synchronization in a separate commit.

src/contact.rs

@@ -742,6 +742,9 @@ impl Contact {
 
         let addr_normalized = addr_normalize(addr);
 
+        if addr_normalized == ContactId::DEVICE_ADDR {
+            return Ok(Some(ContactId::DEVICE));
+        }
         if context.is_self_addr(&addr_normalized).await? {
             return Ok(Some(ContactId::SELF));
         }
@@ -800,8 +803,11 @@ impl Contact {
         ensure!(!addr.is_empty(), "Can not add_or_lookup empty address");
         ensure!(origin != Origin::Unknown, "Missing valid origin");
 
+        if addr.as_ref() == ContactId::DEVICE_ADDR {
+            return Ok((ContactId::DEVICE, Modifier::None));
+        }
         if context.is_self_addr(addr).await? {
-            return Ok((ContactId::SELF, sth_modified));
+            return Ok((ContactId::SELF, Modifier::None));
         }
 
         let mut name = sanitize_name(name);
@@ -2228,6 +2234,10 @@ mod tests {
         assert_eq!(contact.get_name(), stock_str::self_msg(&t).await);
         assert_eq!(contact.get_addr(), ""); // we're not configured
         assert!(!contact.is_blocked());
+
+        let contact = Contact::get_by_id(&t, ContactId::DEVICE).await.unwrap();
+        assert_eq!(contact.get_addr(), "device@localhost");
+        assert!(!contact.is_blocked());
     }
 
     #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -2684,6 +2694,11 @@ mod tests {
             .await
             .unwrap();
         assert_eq!(id, Some(ContactId::SELF));
+
+        let id = Contact::lookup_id_by_addr(&alice.ctx, ContactId::DEVICE_ADDR, Origin::Unknown)
+            .await
+            .unwrap();
+        assert_eq!(id, Some(ContactId::DEVICE));
     }
 
     #[tokio::test(flavor = "multi_thread", worker_threads = 2)]