Adds mcp__perplexity__* to both researcher profiles (generated source-of-truth) and regenerates the agents; adds a generative dispatch-table↔tools parity guard so future provider drift fails CI. Regenerates the agent-size baseline for the +20-byte frontmatter growth.
Fixes#1284
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>