feat(scripts): rebuild the frank-dragoon eval stage after a reboot

/tmp is tmpfs: the 2026-10-18 IOMMU reboot deleted /tmp/halogen-eval mid-A/B and
the off-arm numbers nearly went unreproducible. One command restores the corpus
(wikitext-2 raw test, blanks dropped, 2891 lines / 1287656 B -- the byte count is
the identity check because battery.py sizes haystacks in characters), the 512px
probe PNG, and battery.py itself; WARM=1 also pre-reads the 51.2 GB n-gram table
so a cold page cache cannot masquerade as a measured regression. Must run through
a login shell: uv lives in ~/.local/bin.

scripts/stage-frank-dragoon-eval.sh

@@ -0,0 +1,69 @@
+#!/usr/bin/env bash
+# stage-frank-dragoon-eval.sh — rebuild the /tmp/halogen-eval staging dir that
+# battery-frank-dragoon.py reads. /tmp is tmpfs, so EVERY REBOOT deletes the
+# corpus and the probe image (learned the hard way on 2026-10-18, mid A/B).
+#
+#   Run on Dankclaw through a login shell: uv lives in ~/.local/bin, which a
+#   bare `ssh host script` does not put on PATH.
+#       ssh dankclaw 'bash -lc "/home/dank/serverAppConfigs/scripts/stage-frank-dragoon-eval.sh"'
+#
+# The corpus is the wikitext-2 raw test split with blank lines removed and the
+# rows joined by single newlines (2,891 lines). battery.py sizes its haystacks
+# in CHARACTERS (CPT 4.33), so the byte count IS the identity check across two
+# boots: 1287656 B. If that number changes, the two boots are not comparable.
+set -euo pipefail
+STAGE=/tmp/halogen-eval
+mkdir -p "$STAGE"
+cd "$STAGE"
+
+if [ ! -s wikitext-2-raw-test.txt ]; then
+  uv run --quiet --with pyarrow python3 - <<'PY'
+import pathlib, urllib.request
+import pyarrow.parquet as pq
+
+raw = pathlib.Path("test.parquet")
+url = ("https://huggingface.co/datasets/wikitext/resolve/main/"
+       "wikitext-2-raw-v1/test-00000-of-00001.parquet")
+if not raw.exists() or raw.stat().st_size < 1_000_000:
+    urllib.request.urlretrieve(url, raw)
+
+lines = []
+for text in pq.read_table(raw).column("text").to_pylist():
+    lines.extend(ln for ln in text.split("\n") if ln.strip())
+out = pathlib.Path("wikitext-2-raw-test.txt")
+out.write_text("\n".join(lines) + "\n")
+print("lines", len(lines), "bytes", out.stat().st_size)
+PY
+fi
+
+if [ ! -s red512.b64 ]; then
+  uv run --quiet python3 - <<'PY'
+import base64, struct, zlib
+
+def chunk(tag, data):
+    body = tag + data
+    return struct.pack(">I", len(data)) + body + struct.pack(">I", zlib.crc32(body) & 0xFFFFFFFF)
+
+w = h = 512
+rows = b"\x00" + b"\xdc\x32\x32" * w          # filter 0 + solid color per pixel
+png = (b"\x89PNG\r\n\x1a\n"
+       + chunk(b"IHDR", struct.pack(">IIBBBBB", w, h, 8, 2, 0, 0, 0))
+       + chunk(b"IDAT", zlib.compress(rows * h, 6))
+       + chunk(b"IEND", b""))
+open("red512.b64", "wb").write(base64.b64encode(png))
+print("png bytes", len(png), "b64", len(base64.b64encode(png)))
+PY
+fi
+
+# battery.py reads the corpus and the PNG at import time; ship it here so one
+# command restores the whole stage.
+cp -f "$(dirname "$(readlink -f "$0")")/battery-frank-dragoon.py" battery.py
+chmod +x battery.py
+
+# The 51.2 GB n-gram table is page cache (Pin::None). A reboot leaves it cold,
+# and a cold table throttles prefill — warm it before any measurement.
+if [ "${WARM:-0}" = 1 ]; then
+  time cat /home/dank/models/halogen-v2-abliterated/qwen38-flash-next-ngram.hgn >/dev/null
+fi
+
+ls -l "$STAGE" | sed -n '1,8p'