Add NotHumanSearch and AI Dev Jobs MCP servers

[unitedideas]

Summary

Adds two production MCP servers to the MCPs section:

• NotHumanSearch (General MCPs) - Searchable index of 8,600+ agent-friendly sites filtered for real agent signals (llms.txt, OpenAPI, ai-plugin.json, MCP endpoints). Useful for agents that need to discover other agent-consumable APIs and tools.
• AI Dev Jobs (Development MCPs) - 8,400+ AI/ML engineering jobs aggregated across 489 companies. Tools: search_jobs, get_job, list_companies, get_stats. Useful for developer-focused Copilot workflows around job discovery and market research.

Both servers are live HTTPS JSON-RPC endpoints (no install step), published in the official MCP registry, and follow the same pattern as existing entries like GitHub MCP and Context7.

Test plan

• Entries alphabetized within their respective subsections where natural
• Links resolve (both /mcp endpoints return JSON-RPC-ready responses)
• Descriptions match the concise style of surrounding entries
• No duplicates or existing entries touched