chore: use canonical project URLs

[earguinarena]

Summary

• Replace obsolete organization URLs with the canonical infrastructure-as-decorator identity.
• Add the canonical homepage and documentation URLs to project metadata.
• Update related-project links in README.

Validation

• 227 tests passed.
• pyproject.toml parsed and Project-URL entries verified.
• compileall and git diff --check passed.
• No residual obsolete owner references or generated artifacts are tracked.
• Wheel/sdist build could not run because the environment lacks the build and wheel modules; dependencies were not changed.