Build Provenance Investigator Agent & MCP Firecrawl Integration

Create the 'Content Provenance Investigator' agent. This agent should receive a content fragment and use LlamaIndex for internal content database search. Additionally, integrate a simulated web crawling tool (like Firecrawl) via MCP to search for external matches on the web. Claude Opus 4.1 should then synthesize these findings to generate a provenance report, matching the `ProvenanceResearchTask` format.