Add machine learning resources

[palakgupta29]

Fixes #742

[d-morrison]

Manual review (the automated @claude review can't run here — see the CI note at the bottom).

Content looks good. Thanks for the additions, @palakgupta29 👍

• build, Spellcheck, and lint-changed-files are all green.
• The @james2021islr2e citation key resolves in references.bib.
• The six links are sensible, well-described resources for the new "Machine learning" section.

One minor, optional style point (not blocking): ### Machine learning would be the only Markdown heading in chapters/other-resources.qmd — the rest of the chapter is a flat bullet list, and other groupings (e.g., "Other similar courses at UC Davis:") are introduced with a plain line rather than a heading. For consistency you might either match that plain-intro style (e.g., a bold "Machine learning:" lead-in) or leave the heading if @d-morrison prefers to start adding headings to this chapter. Maintainer's call.

About the red claude-review check: it failed with Could not fetch an OIDC token … Unable to get ACTIONS_ID_TOKEN_REQUEST_URL and an empty ANTHROPIC_API_KEY. That's the standard GitHub restriction that secrets and OIDC tokens are not exposed to workflows triggered by PRs from forks — so anthropics/claude-code-action can't authenticate. It is not a problem with this PR's content and isn't something you can fix from the fork. @d-morrison can get an automated review by pushing this branch to the main repo (a non-fork PR), or just merge on the strength of the green build/spell/lint once the style point above is settled.

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Generated by Claude Code

[github-actions]

👀 Picked up by workflow run #27814527267. R/Quarto/renv setup runs first (~3-5 min); Claude itself responds after that.

[github-actions]

Working tree is clean — no code changes needed (this PR comes from a fork and the content already passes review). My response will be posted as a PR comment.

The triggering event was d-morrison's comment which mentioned `@claude` in inline code ("the automated @claude review can't run here"). That backtick-wrapped mention still fired the webhook and routed me here via the issue_comment trigger, which does have secret access.

Here is my review:

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Automated review here — I was triggered by the `@claude` mention in @d-morrison's comment above (inline-code backticks still fire the webhook, and issue_comment triggers have secret access even for fork PRs, unlike the dedicated claude-review check job).

I've read the diff and the full chapters/other-resources.qmd. I agree with @d-morrison's assessment:

Content: ✅ Good. The six resources are relevant additions for students transitioning into machine learning territory.

Technical:

• @james2021islr2e — confirmed to be in references.bib (per @d-morrison).
• Multi-line continuation lines (e.g. An online version is available for free...) are flush-left, which is consistent with existing multi-line bullets in this file (e.g. the @dobson4e and @statproofbook entries).

One additional observation: four of the six bullets (@james2021islr2e, Stats Learning Notes, ISLR Notes, ISLP Book Club) are specifically about An Introduction to Statistical Learning. The section might read more cohesively if the ISL-focused bullets are grouped together and the two more general entries (Introduction to Machine Learning, DSLC) come last, but this is a very minor presentational point and not blocking.

Style (reinforcing @d-morrison's point): The ### Machine learning Markdown heading is the only section heading in the file — every other grouping uses plain prose or an implicit break. A bold lead-in like **Machine learning:** on its own line would match the "Other similar courses at UC Davis:" pattern. @d-morrison's call.

Nothing blocking from my side. Once the heading style question is resolved, this looks ready.

_{— posted by @claude post-step from workflow run}