Summary

Connects Phenotypic Imaging Bioactivity MCP to the public ToxMCP umbrella docs as a private/local-RC staging module.

What changed

• Adds a conservative Private / Local RC Staging section to the suite README.
• Adds processed-imaging bioactivity guidance to docs/choosing-a-module.md.
• Avoids claiming public release availability while the module repository remains private.
• Cleans up pre-existing public link-check blockers for planned repos and DOI text so the public link-check gate can pass.

Validation

• git diff --check
• GitHub lychee link check passed on PR [codex] Connect phenotypic imaging MCP staging docs #1.