Retire rme's prerequisite appendices in favor of the mds/pds/sds repos

[dem-extra1]

Plan (Ezra, 2026-09-28): rme will eventually drop its prerequisite appendices and refer readers to the shared prerequisite repositories instead. Those repositories become the canonical home for this material:

Repository	Takes over from rme
Morrison-Lab/mds (math)	math-prereqs.qmd, algebra.qmd, calc-derivatives.qmd, calc-integrals.qmd, notation.qmd
Morrison-Lab/pds (probability)	probability.qmd, sec-CLT.qmd
Morrison-Lab/sds (statistics)	estimation.qmd, inference.qmd, intro-MLEs.qmd, bayesian-inference.qmd, basic-statistical-methods.qmd, exploratory-descriptive.qmd, nonparametric-models.qmd

Until then, content lives in both places. Where the two versions differ, the prereq repos take whichever version is more advanced, so rme's copy should not be improved further in isolation.

Steps:

• Finish migrating each appendix into its prereq repo (in progress on the claude/wizardly-brown-zeszu0 branches of mds, pds and sds).
• Decide how rme consumes them: include fragments through git submodules (mds/, pds/, sds/ at the root, the paths the prereq repos are built for), or link out to their published sites.
• Repoint rme's cross-chapter links into the appendices (e.g. probability.qmd#def-variance, estimation.qmd#def-estimation-error) at the new homes. The prereq repos keep rme's #ids so this is a path change, not an id change.
• Remove the duplicated appendix chapters from _quarto-website.yml, _quarto-book.yml and _quarto-handout.yml, and rewrite chapters/appendices-are-prereqs.qmd to point readers at the prereq sites.
• Keep rme-specific material that does not belong in a general prerequisite repo, e.g. the hazard-function section and #def-homosked (see Remove probability-chapter content now duplicated in pds, keep hazard-function and homoskedasticity #1203).

Sub-issue: #1203 (probability chapter).

Posted by Claude Code (AI agent) --- not written by a human.

[d-morrison]

Variable taxonomy and data types chapter (chapters/data.qmd) has been migrated into Morrison-Lab/sds via sds#31 (closes sds#30), now published at https://morrison-lab.github.io/sds/data.html. All original #id anchors (#def-numerical-var, #fig-var-taxonomy, #tbl-wcgs-vartypes, #def-binary, #def-count, etc.) were preserved to allow straightforward link repointing.

Posted by Antigravity (AI agent) --- not written by a human.