Replace archived database courses with CMU 15-445

[Sushanth012]

Summary

• replace the three archived Stanford database courses with CMU 15-445/645
• add a self-study course page based on the complete Fall 2025 offering
• document the Core Systems and C++ prerequisites plus the Project 0 readiness check
• provide Ubuntu VM guidance for Windows because BusTub does not support WSL
• pin project work to the Fall 2025 BusTub tag and explain private repository setup
• document the public Gradescope workflow and academic integrity requirements
• add free supplements for conceptual, object-based, and semistructured data modeling

Rationale

The existing edX entries no longer provide the archived Stanford courses. CMU 15-445/645 is actively maintained and provides complete public lectures, notes, homeworks, project specifications, source code, and delayed autograder access. The course page addresses the environment and preparation concerns raised in the RFC while preserving the identified data-modeling topics through focused supplements.

Validation

• checked all 20 links in the new course page with markdown-link-check
• ran markdownlint-cli2 on the new course page with zero findings
• ran git diff --check
• manually verified the Fall 2025 schedule, assignments, FAQ, syllabus, BusTub tag, environment support, and collaboration policy

Closes #1111

[Dan-Kot]

Just wondering, will you actually learn SQL with these courses or is that secondary?

Overall this looks but it may need more in teaching SQL.

I saw Oracle database course that is a good course, I'm just gonna mention it but this will probably need a SQL academic course Oracle Database course

[edcedcedcedc]

I completely agree. They even provide a Gradescope account to evaluate your homework and labs, but the material is challenging. I'm currently taking the course.