main: keep only what reproduces the manuscript; everything else lives on dev

Removed from main (all preserved on the dev branch): the arXiv build and
its sources, design documents (blueprint, results summary, review responses,
essay drafts), tasks/ and CLAUDE.md, the cover letter and reference tooling,
two unused manuscript figures, and every experiment that feeds no figure or
number in the paper: the collapse null, the sexual-vs-asexual lineage, the
NK speciation variant, the 0.5B single-seed LLM prototypes, the compose and
society experiments with their calibration and pilot runs, and their
configs, runners, tests, figure scripts and PBS jobs. Their result bundles
are moved to results/_archive/ (ignored) so the parquets stay on disk.

Also: plot_llm_speciation reads the s{seed}/ layout; the mating-breadth
plot writes under its bundle name; Makefile targets reduced to the kept
experiments; REPRODUCING.md and README point to dev for the rest.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y64o8FKP7rCuXzC48pxpMm

results/llm_curriculum_v5_stop3/README.md

@@ -3,7 +3,7 @@
 Config `configs/llm/curriculum_v5_stop3.yaml`: the v5 `society` arm (three lineages, six real-dataset
 families in a Latin square, Qwen2.5-1.5B base, rank-16 adapters continued from the parent) with
 recombination switched off from generation 3 (`merge_until: 3`, no veto). Generations 0–2 merge
-obligately; 3–5 never. Pre-registered in `tasks/prereg-llm-society-v4.md` §8h before running.
+obligately; 3–5 never. Pre-registered in `tasks/prereg-llm-society-v4.md on the dev branch` §8h before running.
 Seed 1 local (batch 24 / train batch 2); seeds 2–3 on CX3 via `hpc/llm_curriculum_controls.pbs`
 (batch 48 / train batch 4), as in the v5 campaign. Layout: `results.parquet` (seed 1), `s2/`, `s3/`.