MCP server: foundation package with transport, auth, and test infrastructure

Features

• MCP server: foundation package with transport, auth, and test infrastructure
• MCP server: inbox and thread tools
• MCP server: send and compose tools (send_email, draft_email, dry_run, batch_send, schedule_followup)
• MCP server: intelligence tools (classify_inbound, next_best_action, get_context, batch variants)
• CLI: show changelog summary during molted update

Fixes

• Consent check: return { hasConsent: false } instead of empty array
• Analytics: velocity, deliverability, and stats refresh after sends are processed
• CLI: fix dogfood-reported bugs in domains (500), trace format, and timeline empty
• CLI: helpful error for analytics fatigue; normalize simulate-batch recipients
• Docs: fix safety get help text and skill.md schema
• Docs: remove /docs/ prefix from internal links causing 404s