feat: OpenMesh 基础平台与 MD/PDF 转换技能

- 后端: coworker 智能体框架, WS API, 文件上传, 附件处理
- 前端: Open WebUI, 文件全量走 upload API (含 MD/TXT/JSON 等文本类)
- 技能: md-to-office (pandoc + wkhtmltopdf)
- 修复: 上传文件路径丢失, Agent 搜索浪费, 输出文件跑到 uploads/
- 打包: PyInstaller one-dir, 预打包 pandoc/wkhtmltopdf/chromium

surfaces/gui/e2e/rail-default.spec.ts

@@ -0,0 +1,45 @@
+// UX-038 follow-up (owner ruling 2026-08-21): the right rail starts hidden and the
+// topbar toggle's choice survives a restart. Deep links (artifact chips) force-show
+// transiently without overwriting the stored preference.
+import { expect } from "@playwright/test";
+import { test } from "./fixtures";
+
+async function clearRailPref(page: import("@playwright/test").Page) {
+  await page.goto("/");
+  await page.evaluate(() => {
+    localStorage.setItem("ocw-e2e-rail-default", "1"); // opt out of the fixture seed
+    localStorage.removeItem("coworker:rail-hidden:v1");
+  });
+  await page.reload();
+}
+
+test("rail is hidden by default; the toggle persists across restarts", async ({ page }) => {
+  await clearRailPref(page);
+  await expect(page.getByTestId("rail-toggle-artifacts")).toHaveCount(0);
+
+  // Show it — the choice must survive a reload ("restart").
+  await page.getByRole("button", { name: "Show side panel" }).click();
+  await expect(page.getByTestId("rail-toggle-artifacts")).toBeVisible();
+  await page.reload();
+  await expect(page.getByTestId("rail-toggle-artifacts")).toBeVisible();
+
+  // Hide it — that persists too.
+  await page.getByRole("button", { name: "Hide side panel" }).click();
+  await page.reload();
+  await expect(page.getByTestId("rail-toggle-artifacts")).toHaveCount(0);
+});
+
+test("an artifact chip force-shows the rail without overwriting the hidden preference", async ({ page }) => {
+  await clearRailPref(page);
+  // "show the report" makes the fixture echo carry an [artifact:] chip.
+  await page.getByPlaceholder(/Ask the coworker/).fill("show the report");
+  await page.getByRole("button", { name: "Send" }).click();
+
+  // The transcript's artifact chip opens the viewer even though the rail is hidden.
+  await page.getByTestId("artifact-chip").click();
+  await expect(page.getByTestId("artifact-frame")).toBeVisible();
+
+  // The stored preference is untouched: a reload starts hidden again.
+  await page.reload();
+  await expect(page.getByTestId("rail-toggle-artifacts")).toHaveCount(0);
+});