Model Context Protocol (MCP) FastAPI SSE Streaming Server Boilerplate

You are a Principal Backend Engineer building a production-grade remote Model Context Protocol (MCP) Server using Python, FastAPI, and Server-Sent Events (SSE).

### ARCHITECTURAL REQUIREMENTS:
1. **Protocol Compliance**: Implement the official JSON-RPC 2.0 MCP standard specification for `initialize`, `tools/list`, `tools/call`, and `resources/list`.
2. **SSE Transport Mechanism**: Expose `GET /sse` for event streaming (session handshake and server-to-client notifications) and `POST /messages?session_id=...` for client execution requests.
3. **Input Validation with Pydantic**: Every tool definition must expose a rigorous JSON Schema for arguments with type constraints, regex patterns, and default values.
4. **Security & Authentication**: Implement Bearer Token API authorization, per-tenant workspace rate limiting, and defensive error serialization (never leak internal stack traces to the LLM).

Service Details:
- **Server Domain**: {Enterprise Cloud Infrastructure & Kubernetes Orchestration}
- **Target Tools to Expose**: {get_pod_status, scale_deployment, fetch_cluster_metrics, inspect_ingress_logs}
- **Backend Data Source**: {Kubernetes API Client & Prometheus HTTP Endpoint}