Is your feature request related to a problem? Please describe.
Add Perplexity Search endpoint so the user has another option like Tavily/Exa for quality searches

Describe the solution you'd like
Add the perplexity search endpoint. Currently the Perplexity block only supports the /chat/completions endpoint.

Additional context
Endpoint details https://docs.perplexity.ai/api-reference/search-post
https://docs.perplexity.ai/getting-started/pricing#choosing-the-right-api