Regenerate project page and update advisory board

[zixiaowang17]

Summary

• commit the generated projects.html content for the Linear Model added in Add the Linear Model #6
• add Sourav Chatterjee to the Advisory Board with his Stanford affiliation, homepage, and profile image
• regenerate governance.html from its Markdown source

Root cause

PR #6 updated content/projects.md without committing the corresponding generated projects.html. The build-site workflow rebuilt the page and failed when git diff --exit-code detected that missing generated output.

Impact

The Linear Model project will appear on the published Projects page, the generated-file CI check will pass, and Sourav Chatterjee will appear on the Governance page.

Validation

• python3 tools/build_site.py
• git diff --exit-code
• git diff --check
• local browser preview of governance.html