[CHORE]: Move graphviz_server to mcp-servers/python/graphviz_server

[jonpspri]

Summary

Move the graphviz_server MCP server from the mcp-context-forge monorepo into this repository at mcp-servers/python/graphviz_server/, as part of the MCP server migration tracked in IBM/mcp-context-forge#6228.

What to move

Copy the contents of mcp-servers/python/graphviz_server/ from IBM/mcp-context-forge verbatim:

mcp-servers/python/graphviz_server/
├── Containerfile
├── Makefile
├── README.md
├── pyproject.toml
├── src/
│   └── graphviz_server/
│       ├── __init__.py
│       └── server_fastmcp.py
└── tests/

Dependencies (as-is)

From pyproject.toml:

fastmcp>=3.4.4
pydantic>=2.13.4

The server is moved as-is. Version constraint updates are tracked separately (see sub-issues).

Acceptance criteria

• Server lands at mcp-servers/python/graphviz_server/ in this repository
• pyproject.toml is present and installable (pip install -e mcp-servers/python/graphviz_server)
• Existing tests pass
• CI covers the server (lint + test)
• README updated to reflect new home

References

• Parent issue: [CHORE]: MCP SDK v2 — Update mcp-servers subpackages: FastMCP rename, dependency pins (Step 10/11) mcp-context-forge#6228
• Source: https://github.com/IBM/mcp-context-forge/tree/main/mcp-servers/python/graphviz_server