RAG: MCP Server for knowledge base search

[sre-helmcode]

Description

Create cmd/rag-mcp/main.go — HTTP MCP server exposing:

• search_knowledge tool (query → embed → Qdrant search → return chunks)
• list_documents tool (list org documents by status)

Multi-tenant via X-Org-ID header → maps to Qdrant collection org_{orgID}.

Create internal/runtime/rag_mcp.go for container lifecycle (lazy+persistent).
Create build/rag-mcp/Dockerfile and Makefile targets.

Acceptance Criteria

• MCP server responds to tool calls correctly
• Tenant isolation via X-Org-ID header
• Container lifecycle management (EnsureRagMcp, ConnectToNetwork)
• Dockerfile builds successfully
• Unit tests for MCP handlers