Add naive insertion, fix visualization

ConflictSet.h

@@ -32,6 +32,8 @@ struct ConflictSet {
     /// `end` having length 0 denotes that this range is the single key {begin}.
     /// Otherwise this denotes the range [begin, end)
     Key end;
+    /// Write version must be greater than all write versions in all previous
+    /// calls to `addWrites`
     int64_t writeVersion;
   };
   /// `reads` must be sorted ascending, and must not have adjacent or