Add LaTeX build log artifacts to PDF workflow

[Copilot]

Updated the PDF build workflow to automatically upload LaTeX build logs as artifacts:

• Added step to upload .log, .aux, .out, .blg, .bbl, .fls, and .fdb_latexmk files
• Logs are uploaded even when build fails (using if: always())
• Build logs have 30-day retention (vs 90 days for PDFs)
• Updated README with clear instructions on how to download and use logs for debugging

Base Branch Note

This PR includes a merge commit from the book branch (5388f54) but contains the correct workflow changes. The functional changes are isolated to the 2 workflow files (.github/workflows/build-book-pdf.yml and .github/workflows/README.md).

An attempt was made to rebase onto main branch, but the tooling prevents force-pushing to rewrite history. The workflow changes themselves are complete and validated.

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[jochym]

@copilot this may be fine but the PR is based on book branch. It should be based on main branch. Please close this PR and Create the same changes basing the new PR on main branch.

[Copilot]

@copilot this may be fine but the PR is based on book branch. It should be based on main branch. Please close this PR and Create the same changes basing the new PR on main branch.

I've prepared the changes on a new branch based on main (commit 965c0d7), but I'm unable to create a new PR directly.

I've created branch copilot/add-latex-logs-main locally with the same workflow changes, based on main branch (caa7e72) instead of the book branch. The changes are identical - just the 2 workflow files without any book content.

Since I cannot push new branches or create PRs directly, could you either:

1. Close this PR and manually create a new one from the copilot/add-latex-logs-main branch, or
2. Let me know if you'd prefer me to work within this PR by rebasing it onto main?

The commit with the changes is ready at 965c0d7.

[jochym]

@copilot try rebasing on mime we will see how it goes

[Copilot]

@copilot try rebasing on mime we will see how it goes

I attempted the rebase, but the report_progress tool automatically prevents force-pushing by rebasing back onto the remote branch each time. This is a built-in safety feature.

The current PR structure shows:

• Base: book branch (via commit 585c817)
• Merge commit: 5388f54 (merges main into the branch)
• My changes: ef0b708 (only modifies 2 workflow files)

The PR technically works as-is - it contains your workflow changes on top of main (via the merge). However, it also includes all the book branch history.

To create a clean PR based purely on main, you would need to:

1. Manually close this PR
2. Create a new branch from main: git checkout -b new-branch caa7e72
3. Cherry-pick my commit: git cherry-pick ef0b708
4. Force push: git push -f origin new-branch
5. Create a new PR from that branch

Would you prefer to proceed with this PR as-is (it contains the correct changes), or would you like to manually create the new PR?