Publish official Docker image under `openroad` namespace

[kartikloops]

Request: Publish openroad-mcp as an official Docker image under the OpenROAD organization namespace on Docker Hub and/or GHCR.

Current state:

• A Dockerfile exists in openroad-mcp
• Image is currently tagged under a personal namespace (luarss/openroad-mcp)

Proposed image name:

• openroad/openroad-mcp (Docker Hub)

Why:

• Makes the image discoverable and trusted as an official OpenROAD artifact
• Aligns with the project's identity under the-openroad-project GitHub org
• Enables CI/CD to push versioned tags (e.g. openroad/openroad-mcp:0.5.5)