[Obs AI Assistant] Editing the prompt from contextual insights is not user friendly

Kibana version: 8.16

Describe the bug: The content populated when clicked on "Edit prompt" from contextual insights alerts, is not user friendly.

Before insights are generated from the AI Assistant, the Edit prompt textarea is empty.
After an insight is generated, the "Edit prompt" textarea is populated with an unreadable JSON Object.

Steps to reproduce:

Go to an alert and click on the downarrow for "Help me understand this alert" --> The AI assistant will start generating a response
Click on the 3 dots --> Edit prompt
The textarea will be populated with a JSON object

Expected behavior: The prompt to be edited should be human readable.

Screenshots (if relevant):

"Edit Prompt" before a conversation is triggered:

"Edit Prompt" after a conversation is triggered:

elastic / kibana