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-jsonrpc/src/api/types/events.rs

@@ -285,6 +285,20 @@ pub enum EventType {
     #[serde(rename_all = "camelCase")]
     ChatlistItemChanged { chat_id: Option<u32> },
 
+    /// Inform that the list of accounts has changed (an account removed or added or (not yet implemented) the account order changes)
+    ///
+    /// This event is only emitted by the account manager
+    AccountsChanged,
+
+    /// Inform that an account property that might be shown in the account list changed, namely:
+    /// - is_configured (see is_configured())
+    /// - displayname
+    /// - selfavatar
+    /// - private_tag
+    ///
+    /// This event is emitted from the account whose property changed.
+    AccountsItemChanged,
+
     /// Inform than some events have been skipped due to event channel overflow.
     EventChannelOverflow { n: u64 },
 }
@@ -426,6 +440,8 @@ impl From<CoreEventType> for EventType {
             },
             CoreEventType::ChatlistChanged => ChatlistChanged,
             CoreEventType::EventChannelOverflow { n } => EventChannelOverflow { n },
+            CoreEventType::AccountsChanged => AccountsChanged,
+            CoreEventType::AccountsItemChanged => AccountsItemChanged,
             #[allow(unreachable_patterns)]
             #[cfg(test)]
             _ => unreachable!("This is just to silence a rust_analyzer false-positive"),