fix(installer): require Node 22 for next lane

tools/install-next-lane.test.sh

@@ -12,6 +12,23 @@ MOSAIC_HOME="$TMP/mosaic"
 STATE="$TMP/state"
 LOG="$TMP/npm.log"
 mkdir -p "$FAKE_BIN" "$HOME_DIR" "$STATE"
+REAL_NODE="$(command -v node)"
+export MOSAIC_TEST_REAL_NODE="$REAL_NODE"
+
+cat > "$FAKE_BIN/node" <<'FAKE_NODE'
+#!/usr/bin/env bash
+set -euo pipefail
+if [[ "$*" == *'process.versions.node.split'* ]]; then
+  printf '%s' "${MOSAIC_TEST_NODE_MAJOR:-22}"
+  exit 0
+fi
+if [[ "${1:-}" == "--version" ]]; then
+  printf 'v%s.0.0\n' "${MOSAIC_TEST_NODE_MAJOR:-22}"
+  exit 0
+fi
+exec "${MOSAIC_TEST_REAL_NODE:?}" "$@"
+FAKE_NODE
+chmod +x "$FAKE_BIN/node"
 
 cat > "$FAKE_BIN/npm" <<'FAKE_NPM'
 #!/usr/bin/env bash
@@ -135,6 +152,20 @@ reset_state() {
   rm -f "$STATE"/*
 }
 
+reset_state
+echo "[test] --next rejects Node 20 before any install action"
+if OUTPUT="$(
+  HOME="$HOME_DIR" MOSAIC_HOME="$MOSAIC_HOME" MOSAIC_PREFIX="$PREFIX" MOSAIC_NO_COLOR=1 \
+  MOSAIC_TEST_NPM_LOG="$LOG" MOSAIC_TEST_STATE="$STATE" MOSAIC_TEST_REAL_NODE="$REAL_NODE" \
+  MOSAIC_TEST_NODE_MAJOR=20 PATH="$FAKE_BIN:$PATH" \
+  bash "$ROOT/tools/install.sh" --cli --next --yes --no-auto-launch 2>&1
+)"; then
+  echo "expected Node 20 next-lane install to fail" >&2
+  exit 1
+fi
+grep -qF 'Node.js >= 22 required for the --next lane' <<<"$OUTPUT"
+[[ ! -s "$LOG" ]] || { echo "Node 20 gate ran npm actions" >&2; exit 1; }
+
 reset_state
 echo "[test] --next fast path pins resolved package versions"
 OUTPUT="$(

tools/install.sh

@@ -526,6 +526,10 @@ if [[ "$NODE_MAJOR" -lt 20 ]]; then
   fail "Node.js >= 20 required (found v$(node --version))"
   exit 1
 fi
+if [[ "$FLAG_NEXT" == "true" && "$NODE_MAJOR" -lt 22 ]]; then
+  fail "Node.js >= 22 required for the --next lane (found v$(node --version))"
+  exit 1
+fi
 
 echo ""
 echo "${BOLD}Mosaic Stack Installer${RESET}"