Crawl Pinecone docs and marketing site instead of demo URLs

[zackproser]

Problem

We've got a use case where folks would like to use this app to demonstrate RAG against the Pinecone documentation and marketing site.

Solution

• Update URL targets to allow crawling Pinecone's official docs and Pinecone's marketing site
• Centralize shared configuration parameters for Serverless into a utility that can be loaded wherever needed
• Create the Pinecone Index if it doesn't already exist, suppressing conflict errors if it does already exist.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Infrastructure change (CI configs, etc)
• Non-code change (docs, etc)
• None of the above: (explain here)

Test Plan

Tested locally and will ask the requesting engineer to verify this branch as well.