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/test-p2p-host.ts

@@ -0,0 +1,42 @@
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { mkdir } from "node:fs/promises";
+import { TempDir } from "./helpers/temp.ts";
+import { initSettingsFile, applyP2pSettings } from "./helpers/settings.ts";
+import { startP2pRelay, stopP2pRelay, isLocalP2pRelay } from "./helpers/docker.ts";
+import { startCliInBackground } from "./helpers/backgroundCli.ts";
+
+test("p2p-host: starts and becomes ready", async () => {
+    const relay = process.env["RELAY"] ?? "ws://localhost:4000/";
+    const roomId = process.env["ROOM_ID"] ?? `room-${Date.now()}`;
+    const passphrase = process.env["PASSPHRASE"] ?? "test";
+    const appId = process.env["APP_ID"] ?? "self-hosted-livesync-cli-tests";
+    const useInternalRelay = process.env["USE_INTERNAL_RELAY"] !== "0";
+
+    await using workDir = await TempDir.create("livesync-cli-p2p-host");
+    const vaultDir = workDir.join("vault-host");
+    const settingsFile = workDir.join("settings-host.json");
+    await mkdir(vaultDir, { recursive: true });
+
+    let relayStarted = false;
+    if (useInternalRelay && isLocalP2pRelay(relay)) {
+        await startP2pRelay();
+        relayStarted = true;
+    }
+
+    try {
+        await initSettingsFile(settingsFile);
+        await applyP2pSettings(settingsFile, roomId, passphrase, appId, relay);
+        const host = startCliInBackground(vaultDir, "--settings", settingsFile, "p2p-host");
+        try {
+            await host.waitUntilContains("P2P host is running", 20000);
+            assert(host.combined.includes("P2P host is running"));
+        } finally {
+            await host.stop();
+        }
+    } finally {
+        if (relayStarted) {
+            await stopP2pRelay().catch(() => {});
+        }
+    }
+});