Eliminate remaining Electron 8 deprecations

* Change systemPreferences.isDarkMode() to nativeTheme.shouldUseDarkColors

* Remove vibrancy parameter to BrowserWindow

* Update curve25519-n; removes context-aware deprecation warning

* Set app.allowRendererProcessReuse = true to remove warning

* Move from deprecated setters to direct property set

* Serialized sender certificates: Store less, store plain object

* isMenuBarAutoHide -> autoHideMenuBar

* UUID: Fix sealed sender indicator on message details screen

* Data._cleanData: Remove function keys, handle null in array

Also:
- run _cleanData when saving attachment download jobs
- remove job from jobs table when the send itself throws error

* _cleanData: Don't dig into strings, booleans, or numbers

* getPropsForMessageDetail: Make it clear what we're reducing

Co-authored-by: Ken Powers <ken@signal.org>

js/models/messages.js

@@ -230,9 +230,11 @@
 
       const unidentifiedLookup = (
         this.get('unidentifiedDeliveries') || []
-      ).reduce((accumulator, item) => {
+      ).reduce((accumulator, uuidOrE164) => {
         // eslint-disable-next-line no-param-reassign
-        accumulator[item] = true;
+        accumulator[
+          ConversationController.getConversationId(uuidOrE164)
+        ] = true;
         return accumulator;
       }, Object.create(null));