Exa AI + Perplexity Integration

Keep Exa AI and Perplexity aligned: when ai events happen in one, update the other automatically.

Example: when Perplexity's "Watch Models" fires, WEXTL can "List Contents" in Exa AI. Exa AI has 4 actions (including List Contents, Make an API Call, and Perform a Search); Perplexity has 12 actions (including Create Agent Response, Create Async Sonar Request, and Create Contextualized Embeddings).