docs: move readme

Author: theboxer

core/components/modai/README.md renamed to README.md

@@ -20,7 +20,7 @@ MODX’s modAI Extra works with the following Extras if installed:
 
 ## Configuration
 
-After installing the Extra, update the `modai.chatgpt_key` with your ChatGPT API key. (Filter by the `modai` namespace to make finding it easier.)
+After installing the Extra, update the `modai.chatgpt.key` with your ChatGPT API key. (Filter by the `modai` namespace to make finding it easier.)
 
 The default fields modAI enables in the `modai.res.fields` setting are longtitle, description, introtext/summary, and content. Attach modAI to other default fields in this setting.