feat: wire native Codex UI as /console entry, keep classic console at /console-classic

- Vendor codex-ui-stack host/ as cloud/codex-ui-host/ (original/ not vendored, 650MB)
- Bridge emulates 7 methods missing in codex 0.164.0-alpha.9, exposes 29
  experimental-protocol methods (150 -> 179), Linux binary candidates,
  read-only POST /__codex_git
- GET /console 302s to the UI host (:8095) when reachable, else falls back
  to the classic React console; GET /console-classic always serves it
- Alignment tables: docs/codex-native-ui-alignment.md
- Tests: test_console 7, new test_codex_ui_host 4, handler method pin 247 -> 249

cloud/codex-ui-host/host/projectless.mjs

@@ -0,0 +1,62 @@
+/**
+ * Projectless thread workspaces.
+ *
+ * Codex keeps two kinds of conversation: one attached to a project directory and
+ * one that starts from nothing. The desktop main process owns the second kind —
+ * it picks a folder under the user's workspace root, creates it, and hands the
+ * paths back to the renderer through `projectlessThreads.createPaths`.
+ *
+ * The browser cannot touch the filesystem, so the Node host does it here and
+ * exposes the same three paths over HTTP:
+ *
+ *   cwd             the directory this conversation runs in
+ *   outputDirectory where generated files land (same folder)
+ *   workspaceRoot   the shared root that contains every thread
+ *
+ * Layout mirrors the desktop app: <root>/<YYYY-MM-DD>/<slug>
+ */
+
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+export const WORKSPACE_ROOT =
+  // Linux server default: ~/Codex. The desktop default ~/Documents/Codex
+  // does not exist on a server, so it is not used here.
+  process.env.CODEX_WEB_WORKSPACE_ROOT || path.join(os.homedir(), "Codex");
+
+export function ensureWorkspaceRoot() {
+  fs.mkdirSync(WORKSPACE_ROOT, { recursive: true });
+  return WORKSPACE_ROOT;
+}
+
+/** Lowercase, collapse anything awkward, keep CJK, cap the length. */
+function slugify(value) {
+  const text = String(value ?? "").trim();
+  if (!text) return "";
+  return text
+    .toLowerCase()
+    .replace(/[^\p{Letter}\p{Number}]+/gu, "-")
+    .replace(/^-+|-+$/g, "")
+    .slice(0, 40);
+}
+
+export function createProjectlessPaths({ directoryName, prompt } = {}) {
+  const root = ensureWorkspaceRoot();
+  const day = new Date().toISOString().slice(0, 10);
+  const base = slugify(directoryName) || slugify(prompt) || "thread";
+
+  let dir = path.join(root, day, base);
+  let suffix = 1;
+  while (fs.existsSync(dir)) {
+    suffix += 1;
+    dir = path.join(root, day, `${base}-${suffix}`);
+  }
+  fs.mkdirSync(dir, { recursive: true });
+
+  return { cwd: dir, outputDirectory: dir, workspaceRoot: root };
+}
+
+export function readWorkspaceRoot() {
+  return { workspaceRoot: ensureWorkspaceRoot() };
+}