Add Cortex Agents REST API and managed MCP server documentation

[iamontheinet]

Summary

Adds two new Snowflake documentation entries under content/snowflake/docs/:

• cortex-agents-rest-api — REST API for creating, managing, and running Cortex Agent objects with built-in tools (Cortex Analyst, Cortex Search, web search, SQL execution) and custom UDF/stored procedure tools
• cortex-agents-mcp — Snowflake-managed MCP (Model Context Protocol) server for exposing Cortex Analyst, Cortex Search, Cortex Agents, SQL execution, and custom tools over the MCP standard with OAuth auth and RBAC governance

Directory structure

content/snowflake/docs/
├── cortex-agents-rest-api/DOC.md   (269 lines)
└── cortex-agents-mcp/DOC.md        (215 lines)

Validation

$ chub build content/ --validate-only
Valid: 1555 docs, 7 skills, 2 warnings

(2 pre-existing warnings from landingai skills — 0 new warnings from this PR)

Test plan

• Verify node cli/bin/chub build content/ --validate-only passes with 0 new warnings
• Confirm YAML frontmatter matches expected schema (name, description, metadata fields)
• Check each DOC.md is under 500 lines (269 + 215 = 484 total)
• Verify directory structure follows content/<company>/docs/<product>/DOC.md convention