remember the pre-flight answers between runs

The --only flag worked, in that it reached the section — but reaching it meant
answering four pre-flight questions first, every time, which is not usable for
working on one section. The same problem was already there without --only: a
resumed run re-asked the role, the account and the Officer path that it had been
told on the previous pass.

Answers are saved beside the progress file and loaded before anything is asked.
The environment still wins over what was saved, so SETUP_USERNAME=x on the
command line overrides it, and --reask throws the file away and asks again.

Read as assignments rather than sourced. The file sits next to the script and is
read by a run that is already root; sourcing it would make it executable content
in a place nothing guards.

Second run now goes straight through pre-flight, printing what it remembered, to
the one step asked for.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

scripts/setup/machine-setup/machine-setup.sh

@@ -12,6 +12,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROGRESS_FILE="$SCRIPT_DIR/.setup-progress"
+ANSWERS_FILE="$SCRIPT_DIR/.setup-answers"
 
 # --only <step> runs one section and nothing else, for working on it. Pre-flight
 # still runs, because every section needs what it establishes — the system, the
@@ -27,12 +28,16 @@ while [[ $# -gt 0 ]]; do
       ONLY_STEP="${1#*=}"
       shift
       ;;
+    --reask)
+      RE_ASK=1
+      shift
+      ;;
     -l | --list)
       grep -oP '^step "\K[^"]+' "${BASH_SOURCE[0]}"
       exit 0
       ;;
     -h | --help)
-      echo "usage: machine-setup.sh [--only <step>] [--list]"
+      echo "usage: machine-setup.sh [--only <step>] [--reask] [--list]"
       exit 0
       ;;
     *) echo "unknown option: $1" >&2 && exit 2 ;;
@@ -78,6 +83,10 @@ echo -e "${BOLD}╔════════════════════
 echo -e "${BOLD}║          Machine Setup                           ║${NC}"
 echo -e "${BOLD}╚══════════════════════════════════════════════════╝${NC}"
 
+# Anything answered on a previous run, unless --reask says to ask again.
+[[ -n "${RE_ASK:-}" ]] && rm -f "$ANSWERS_FILE"
+load_answers
+
 detect_os
 echo ""
 info "Machine:  ${OS_NAME} (${ARCH})"
@@ -123,6 +132,8 @@ else
   info "Officer:  ${OFFICER_ROOT}"
 fi
 
+save_answers
+
 # Always, and outside any step: everything below reads this index — core utils,
 # the fastfetch PPA, the Docker repo — and `step` skips a step whose name is
 # already in the progress file. With the refresh inside one of those, a resumed