Website update notes — course/student source split

This revision uses the supplied bbf.zip as the authoritative starting snapshot.

Architecture established

• src/course/ is course-owned infrastructure.
• src/student/ is student-owned implementation code.
• src/solve.py remains a course-owned launcher.
• project.json remains at the repository root and its schema is unchanged by this restructuring.

Pages changed

• _index.md
• repository.md
• program-interface.md
• graph-interface.md
• minimum-vertex-cover.md
• traveling-salesperson.md
• graph-coloring.md
• longest-path.md
• maximum-clique.md
• checkpoints/_index.md
• README.md

Also corrected

The main _index.md now links directly to the split Checkpoint 1 and Final pages and uses the current names/descriptions for Checkpoints 3 and 4. The Classroom 50 link is also resolved to the current assignment URL used on repository.md.

Files worth reviewing/removing from published Hugo content

The supplied snapshot contains apparent older/archive copies, including:

• _index copy.md
• checkpoints.md
• checkpoints-monolithic-backup.md
• several specs_*.md files

They were preserved in this returned snapshot rather than deleted automatically. If they live directly in the Hugo content directory, consider moving them outside published content so they cannot create duplicate/stale pages.