Add variable wrapping "{{ }}" to Nodes' Synthax Highlighter

[ch0m5]

Simply put, add Synthax Highlighter for text wrapped within {{ }} so that is painted on a different color. That way it is easier to visualize variables present in a Dialogue or other Node types.

Example use case below, which also includes number highlighting because it's relevant for what the text is used for, but what could be "globally present" for Nodes is variable highlighting, given they can be used anywhere afaik: