docs: add top-level Security Policy page across all languages

Create a dedicated Security Policy page (docs/{en,pt-BR,ko,ar}/security.mdx)
with vulnerability reporting instructions pointing to the Bugcrowd VDP
(crewai-vdp-ess@submit.bugcrowd.com), consistent with the updated security
policy from PR #5096.

The page is added to the Documentation tab navigation (after Telemetry)
across all versions and languages in docs.json.

This is a top-level security page, not buried inside MCP docs.

docs/en/mcp/security.mdx

@@ -156,7 +156,19 @@ If you are developing an MCP server that CrewAI agents might connect to, conside
 - **Adherence to MCP Authorization Spec**: If implementing authentication and authorization, strictly follow the [MCP Authorization specification](https://modelcontextprotocol.io/specification/draft/basic/authorization) and relevant [OAuth 2.0 security best practices](https://datatracker.ietf.org/doc/html/rfc9700).
 - **Regular Security Audits**: If your MCP server handles sensitive data, performs critical operations, or is publicly exposed, consider periodic security audits by qualified professionals.
 
-## 5. Further Reading
+## 5. Reporting Security Vulnerabilities
+
+If you discover a security vulnerability in CrewAI, please report it responsibly through our Bugcrowd Vulnerability Disclosure Program (VDP):
+
+**Submit reports to:** [crewai-vdp-ess@submit.bugcrowd.com](mailto:crewai-vdp-ess@submit.bugcrowd.com)
+
+<Warning>
+**Do not** disclose vulnerabilities via public GitHub issues, pull requests, or social media. Reports submitted via channels other than Bugcrowd will not be reviewed.
+</Warning>
+
+For full details, see our [Security Policy](https://github.com/crewAIInc/crewAI/blob/main/.github/security.md).
+
+## 6. Further Reading
 
 For more detailed information on MCP security, refer to the official documentation:
 - **[MCP Transport Security](https://modelcontextprotocol.io/docs/concepts/transports#security-considerations)**