feat: add AccountsChanged and AccountsItemChanged events (#6118)

- **feat: add `AccountsChanged` and `AccountsItemChanged` events**
- **emit event and add tests**

closes #6106

TODO:
- [x] test receiving synced config from second device
- [x] bug: investigate how to delay the configuration event until it is
actually configured - because desktop gets the event but still shows
account as if it was unconfigured, maybe event is emitted before the
value is written to the database?
- [x] update node bindings constants

deltachat-ffi/src/lib.rs

@@ -569,6 +569,8 @@ pub unsafe extern "C" fn dc_event_get_id(event: *mut dc_event_t) -> libc::c_int
         EventType::AccountsBackgroundFetchDone => 2200,
         EventType::ChatlistChanged => 2300,
         EventType::ChatlistItemChanged { .. } => 2301,
+        EventType::AccountsChanged => 2302,
+        EventType::AccountsItemChanged => 2303,
         EventType::EventChannelOverflow { .. } => 2400,
         #[allow(unreachable_patterns)]
         #[cfg(test)]
@@ -601,8 +603,10 @@ pub unsafe extern "C" fn dc_event_get_data1_int(event: *mut dc_event_t) -> libc:
         | EventType::ConfigSynced { .. }
         | EventType::IncomingMsgBunch { .. }
         | EventType::ErrorSelfNotInGroup(_)
-        | EventType::AccountsBackgroundFetchDone => 0,
-        EventType::ChatlistChanged => 0,
+        | EventType::AccountsBackgroundFetchDone
+        | EventType::ChatlistChanged
+        | EventType::AccountsChanged
+        | EventType::AccountsItemChanged => 0,
         EventType::IncomingReaction { contact_id, .. }
         | EventType::IncomingWebxdcNotify { contact_id, .. } => contact_id.to_u32() as libc::c_int,
         EventType::MsgsChanged { chat_id, .. }
@@ -676,6 +680,8 @@ pub unsafe extern "C" fn dc_event_get_data2_int(event: *mut dc_event_t) -> libc:
         | EventType::AccountsBackgroundFetchDone
         | EventType::ChatlistChanged
         | EventType::ChatlistItemChanged { .. }
+        | EventType::AccountsChanged
+        | EventType::AccountsItemChanged
         | EventType::ConfigSynced { .. }
         | EventType::ChatModified(_)
         | EventType::WebxdcRealtimeAdvertisementReceived { .. }
@@ -751,6 +757,8 @@ pub unsafe extern "C" fn dc_event_get_data2_str(event: *mut dc_event_t) -> *mut
         | EventType::IncomingMsgBunch { .. }
         | EventType::ChatlistItemChanged { .. }
         | EventType::ChatlistChanged
+        | EventType::AccountsChanged
+        | EventType::AccountsItemChanged
         | EventType::WebxdcRealtimeAdvertisementReceived { .. }
         | EventType::EventChannelOverflow { .. } => ptr::null_mut(),
         EventType::ConfigureProgress { comment, .. } => {