Add customer-reference-request skill

[Satya8208]

Summary

• Adds a customer-reference-request composite skill for B2B customer proof workflows.
• Covers candidate scoring, proof-motion selection, permission-safe asks, reference-call prep, quote/logo approval, follow-ups, and tracking fields.
• Emphasizes approval rights, source-supported claims, private vs public use, and a graceful opt-out.

Testing

• npm run build:index
• npm run ci