Migrate CLI E2E tests to Node.js 26

Run the CLI subprocess suites and benchmark tools as native TypeScript with
node:test, and move them under test/e2e-cli.

Update CI and Compose runners, run local smoke tests on Linux, macOS, and
Windows, and collect source-mapped CLI coverage with c8.

test/e2e-cli/bench-run-item1.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+RESULTS_ROOT="${SCRIPT_DIR}/bench-results"
+TIMESTAMP="$(date +%Y%m%d-%H%M%S)"
+OUT_DIR="${RESULTS_ROOT}/${TIMESTAMP}"
+
+mkdir -p "${OUT_DIR}"
+
+echo "[bench-wrapper] output directory: ${OUT_DIR}"
+
+echo "[bench-wrapper] running p2p benchmark"
+(
+  cd "${SCRIPT_DIR}"
+  BENCH_RESULT_JSON="${OUT_DIR}/p2p.json" node run-task.ts bench:p2p
+)
+
+echo "[bench-wrapper] running couchdb benchmark with RTT ${BENCH_COUCHDB_RTT_MS:-default} ms (emulating HTTP network latency)"
+(
+  cd "${SCRIPT_DIR}"
+  BENCH_RESULT_JSON="${OUT_DIR}/couchdb.json" node run-task.ts bench:couchdb
+)
+
+cat > "${OUT_DIR}/README.txt" <<EOF
+Bench wrapper result set
+
+Generated at: ${TIMESTAMP}
+Directory: ${OUT_DIR}
+
+Files:
+- p2p.json
+- couchdb.json
+EOF
+
+echo "[bench-wrapper] verify outputs by cat"
+echo "========== ${OUT_DIR}/README.txt =========="
+cat "${OUT_DIR}/README.txt"
+echo "========== ${OUT_DIR}/p2p.json =========="
+cat "${OUT_DIR}/p2p.json"
+echo "========== ${OUT_DIR}/couchdb.json =========="
+cat "${OUT_DIR}/couchdb.json"
+
+echo "[bench-wrapper] done"
+echo "[bench-wrapper] result directory: ${OUT_DIR}"