feat: Render diffs in email notifications (#4164)

* deps

* diffCompact

* Diffs in email

* test

* fix: Fade deleted images
fix: Don't include empty paragraphs as context
fix: Allow for same image multiple times and refactor

* Remove target _blank

* fix: Table heading incorrect color

shared/editor/components/Styles.ts

@@ -1035,7 +1035,7 @@ table {
   }
 
   th {
-    background: ${props.theme.tableHeaderBackground};
+    background: transparent;
   }
 
   td,
@@ -1284,6 +1284,10 @@ del {
   text-decoration: strikethrough;
 }
 
+del img {
+  opacity: .5;
+}
+
 @media print {
   .placeholder:before,
   .block-menu-trigger,