test: add script to run example livebooks against local checkout

scripts/test-livebooks.sh extracts the Elixir cells from each notebook
in notebooks/, repoints the `{:emily, "~> x"}` Mix.install dependency at
the working tree (a path dep, so the NIF is built from source and the
notebook runs against local code), and runs each headless with `elixir`,
reporting PASS/FAIL/SKIP plus per-notebook logs.

Mirrors the standalone-Mix.install pattern in scripts/qwen3_conformance.exs.
Notebooks are run, not interacted with — Kino form/input cells (e.g. the
Whisper audio recorder) don't fire, but surrounding setup/inference does.

Author: ausimian

scripts/test-livebooks.sh

@@ -0,0 +1,105 @@
+#!/usr/bin/env bash
+# Smoke-test the example livebooks against the LOCAL emily checkout.
+#
+# For each notebook in notebooks/, this extracts its Elixir cells,
+# repoints the `{:emily, "~> x"}` Mix.install dependency at this repo (as
+# a `path:` dep, so the notebook exercises the working tree — including a
+# from-source NIF build), and runs the result headlessly with `elixir`.
+# A notebook passes if it runs to completion with exit code 0.
+#
+# Notes:
+#   * First run downloads model checkpoints via Bumblebee (cached under
+#     ~/Library/Caches/bumblebee afterwards) and compiles emily's NIF, so
+#     it needs network + disk and can take several minutes per notebook.
+#   * Cells render Kino widgets; outside Livebook those just evaluate to
+#     structs. Notebooks are *run*, not interacted with — anything gated
+#     behind a Kino form/input (e.g. recording audio in the Whisper
+#     notebook) won't fire, but the surrounding setup/inference still does.
+#
+# Usage:
+#   scripts/test-livebooks.sh                                  # all notebooks
+#   scripts/test-livebooks.sh distilbert_qa nomic_embeddings   # a subset
+#
+# Env:
+#   LIVEBOOK_TIMEOUT   per-notebook timeout, seconds (default 1200)
+#   LIVEBOOK_SKIP      space-separated notebook names to skip
+#   EMILY_CACHE        MLX/NIF cache dir (passed through to the build)
+
+set -uo pipefail
+
+REPO="$(cd "$(dirname "$0")/.." && pwd)"
+NB_DIR="$REPO/notebooks"
+TIMEOUT="${LIVEBOOK_TIMEOUT:-1200}"
+SKIP=" ${LIVEBOOK_SKIP:-} "
+
+if ! command -v elixir >/dev/null 2>&1; then
+  echo "error: elixir not on PATH" >&2
+  exit 2
+fi
+
+# Selection: explicit notebook basenames, or every *.livemd.
+if [[ $# -gt 0 ]]; then
+  names=("$@")
+else
+  names=()
+  for f in "$NB_DIR"/*.livemd; do names+=("$(basename "$f" .livemd)"); done
+fi
+
+# Print the contents of every ```elixir fenced block, blank-line separated.
+extract_cells() {
+  awk '
+    /^```elixir[[:space:]]*$/ { inblock=1; next }
+    /^```[[:space:]]*$/       { if (inblock) { inblock=0; print "" }; next }
+    inblock                   { print }
+  ' "$1"
+}
+
+pass=()
+fail=()
+skip=()
+log_dir="$(mktemp -d "${TMPDIR:-/tmp}/emily-livebooks.XXXXXX")"
+echo "emily: $REPO (path dep)"
+echo "logs:  $log_dir"
+echo
+
+for name in "${names[@]}"; do
+  nb="$NB_DIR/$name.livemd"
+  if [[ ! -f "$nb" ]]; then
+    echo ">> $name: NOT FOUND"
+    fail+=("$name")
+    continue
+  fi
+  if [[ "$SKIP" == *" $name "* ]]; then
+    echo ">> $name: SKIP"
+    skip+=("$name")
+    continue
+  fi
+
+  script="$log_dir/$name.exs"
+  out="$log_dir/$name.out"
+  # Extract the cells and repoint the emily dependency at this checkout.
+  extract_cells "$nb" \
+    | sed "s|{:emily,[^}]*}|{:emily, path: \"$REPO\"}|" \
+    > "$script"
+
+  printf ">> %-28s running (timeout %ss) ... " "$name" "$TIMEOUT"
+  start=$SECONDS
+  if timeout "$TIMEOUT" elixir "$script" >"$out" 2>&1; then
+    echo "PASS ($((SECONDS - start))s)"
+    pass+=("$name")
+  else
+    code=$?
+    echo "FAIL (exit $code, $((SECONDS - start))s)"
+    tail -n 25 "$out" | sed 's/^/   | /'
+    fail+=("$name")
+  fi
+done
+
+echo
+echo "==================== livebook results ===================="
+printf "PASS (%d): %s\n" "${#pass[@]}" "${pass[*]:-}"
+printf "FAIL (%d): %s\n" "${#fail[@]}" "${fail[*]:-}"
+printf "SKIP (%d): %s\n" "${#skip[@]}" "${skip[*]:-}"
+echo "logs in $log_dir"
+
+[[ ${#fail[@]} -eq 0 ]]