Unwrap the Brontë corpus and launch the 1.7B rung

Operator: "start the 1.7b training."

The 0.6B adapter learned the Gutenberg transcription's ~70-character line breaks
along with the prose -- its output wrapped at a mid-length-line ratio of 0.85
against the base model's 0.00. That is typography rather than style, and every
further rung would have inherited it, so the corpus is reflowed before rung 2
rather than after the sweep.

The reflow joins 57,430 of 85,380 paragraph blocks and keeps 27,950. Verse is the
hazard a blind join would destroy, so the decision is per block by median line
length: blocks whose lines cluster near the wrap width are flowed prose, blocks of
consistently short lines keep their breaks. Every kept multi-line block in the
sample was genuinely verse with its lineation intact. No line ended in a lone
hyphen, so the space-join could not split a word across lines. The acceptance
check is content identity -- " ".join(text.split()) byte-identical before and
after -- and it passed on all 852 records, proving only whitespace changed.

Concrete cost of the old defect: 5.7% of the training budget was newline tokens.
The same words pack to 5,210,112 tokens unwrapped against 5,525,504 wrapped.

The 1.7B run is live at 159 steps and roughly 18.7 s/it. Everything but the
carrier and the corpus is held from the 0.6B run: seed 4919, rank 32, lr 1e-4, seq
4096, batch 1 by accum 8, one epoch, eval and save every 25 steps so the minimum
is located rather than assumed.

That corpus change is a second variable and it is named as one. A 0.6B-vs-1.7B
comparison is descriptive, not attributable, until the chained 0.6B rerun on the
same unwrapped corpus lands behind it -- gated on the 1.7B actually producing an
adapter, because a chain that fires on failure turns one lost run into two.
"Did sense come back at 1.7B" is a within-arm reading and survives the confound;
any between-rung delta does not.

The original wrapped corpus is untouched, so the 0.6B run's pinned corpus sha
3959036cf851bf62 stays reproducible.

scripts/r49-corpus/chain-0p6b-unwrapped.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+# Chained after the 1.7B rung: re-run the 0.6B carrier on the SAME unwrapped corpus.
+#
+# The 1.7B run moved two variables at once -- carrier size AND corpus typography --
+# because the unwrap could not wait if every further rung was to avoid inheriting the
+# Gutenberg line breaks. That makes a 0.6B-vs-1.7B comparison descriptive rather than
+# attributable, which is fine for "did sense come back" (a within-arm reading) and not
+# fine for anything quantitative between rungs.
+#
+# This closes that hole for the price of ~36 minutes on an idle experimental box:
+# 0.6B on the unwrapped corpus, seed 4919, everything else held. Then carrier size is
+# the ONLY difference between this and h02-1p7b-1ep, and the sweep is single-variable
+# again.
+#
+# ⚠ Gated on the 1.7B run having actually produced an adapter. If that run died, this
+# must not quietly start and consume the box; a chain that fires on failure turns one
+# lost run into two.
+set -uo pipefail
+PREV=/home/infra-ops/r49-runs/h02-1p7b-1ep
+OUT=/home/infra-ops/r49-runs/h02-0p6b-1ep-unwrapped
+LOG=$OUT/train.log
+CHAINLOG=/home/infra-ops/r49-runs/chain-0p6b-unwrapped.log
+
+exec >> "$CHAINLOG" 2>&1
+echo "=== $(date -Is) chain armed, waiting on $PREV"
+while [ -f "$PREV/run.pid" ] && kill -0 "$(cat "$PREV/run.pid")" 2>/dev/null; do sleep 60; done
+echo "=== $(date -Is) 1.7B run finished"
+
+if [ ! -f "$PREV/adapter/adapter_model.safetensors" ]; then
+  echo "=== REFUSING to chain: $PREV produced no adapter -- the 1.7B run did not succeed"
+  exit 1
+fi
+apps=$(nvidia-smi --query-compute-apps=pid --format=csv,noheader | tr -d '[:space:]')
+if [ -n "$apps" ]; then
+  echo "=== REFUSING to chain: GPU not clear"
+  nvidia-smi --query-compute-apps=pid,process_name,used_memory --format=csv
+  exit 1
+fi
+
+mkdir -p "$OUT"
+echo "# launched $(date -Is) Qwen3-0.6B-Base, 1 epoch, seed 4919, UNWRAPPED corpus (single-variable partner to h02-1p7b-1ep)" > "$LOG"
+setsid nohup /home/infra-ops/ml/.venv/bin/python /home/infra-ops/r49-prep/train_voice_lora.py \
+  --corpus /home/infra-ops/r49-corpus-renamed-unwrapped \
+  --base /home/infra-ops/carriers/Qwen3-0.6B-Base \
+  --seed 4919 --epochs 1 --eval-steps 25 --save-steps 25 \
+  --out "$OUT" >> "$LOG" 2>&1 < /dev/null &
+echo $! > "$OUT/run.pid"
+echo "=== $(date -Is) chained 0.6B launched pid $(cat "$OUT/run.pid") -> $LOG"