Diagrams MCP

Generate diagrams using multiple rendering engines. **mingrammer/diagrams** (cloud architecture): Use search_nodes to find components by keyword (returns import paths), or browse with list_providers -> list_services -> list_nodes. Read the diagrams://reference/diagram, diagrams://reference/edge, and diagrams://reference/cluster resources for constructor options and usage examples. Then render_diagram to produce images. **Mermaid** (flowcharts, sequence, class, ER, state, Gantt): Read diagrams://reference/mermaid for syntax. Then render_mermaid with a definition string. **PlantUML** (sequence, class, component, activity, state, deployment): Read diagrams://reference/plantuml for syntax. Then render_plantuml with a definition string. **Cross-provider equivalence**: Use find_equivalent to find equivalent services across providers (e.g. find_equivalent('EC2', 'gcp')), or list_categories to see all mapped infrastructure roles. **Tool selection**: Use render_diagram for cloud architectu