New page at /mcp-servers to register, view, and manage MCP server
instances. Shows endpoint config, enabled tools, and access tokens
with reveal/regenerate controls. Includes McpServerConfig model in
compliance-core, MongoDB collection accessor, server functions for
list/add/delete/regenerate-token, sidebar nav entry, and full CSS.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>