Add enterprise section for on-premises deployment

- Add Enterprise Use section mentioning on-prem deployment availability
- Include link to book demo at https://reflex.dev/pricing/
- Addresses GitHub comment from @adhami3310 on PR #1549

Co-Authored-By: khaleel@reflex.dev <khaleel.aladhami@gmail.com>

Author: devin-ai-integration[bot]

docs/ai_builder/integrations/mcp.md

@@ -74,3 +74,7 @@ Note: Codex requires MCP servers to communicate over stdio. The `@modelcontextpr
 ## Available Tools
 
 The Reflex MCP server provides tools for accessing component documentation and Reflex documentation through standardized MCP capabilities.
+
+## Enterprise Use
+
+For enterprise customers requiring on-premises deployment of the Reflex MCP server, please [book a demo](https://reflex.dev/pricing/) to discuss your requirements.