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/cloud-signin-placement.spec.ts

@@ -0,0 +1,43 @@
+// Regression guard (shipped once, 2026-07-09; reshaped by §26): cloud sign-in must be
+// reachable by a FRESH user. The sidebar account row is the permanent sign-in home —
+// always visible, never below any fold — and every signed-out one-click pane carries a
+// real Sign-in button, not a hint pointing at another page.
+import { expect } from "@playwright/test";
+import { test } from "./fixtures";
+
+async function openConnectors(page) {
+  await page.goto("/");
+  await page.getByTestId("account-row").click();
+  await page.getByTestId("account-menu").getByRole("button", { name: "Connectors", exact: true }).click();
+}
+
+test("the account row is always visible and signs in from its menu", async ({ page }) => {
+  await page.goto("/");
+  const row = page.getByTestId("account-row");
+  await expect(row).toBeVisible();
+  await expect(row).toContainText("Not signed in");
+
+  await row.click();
+  await page.getByTestId("account-sign-in").click();
+  await expect(row).toContainText("Rohit", { timeout: 10_000 });
+
+  // Sign out is right there in the same menu once signed in.
+  await row.click();
+  await expect(
+    page.getByTestId("account-menu").getByRole("button", { name: "Sign out" }),
+  ).toBeVisible();
+});
+
+test("signed-out one-click pane signs in inline, then connects", async ({ page }) => {
+  await openConnectors(page);
+  // Fresh user path: Available → Connect → the pane must offer sign-in itself.
+  await page
+    .getByTestId("connector-gmail")
+    .getByRole("button", { name: "Connect", exact: true })
+    .click();
+  await page.getByTestId("inline-cloud-sign-in").click();
+  // The mock signs in instantly; the section's poll re-renders the pane armed.
+  await expect(
+    page.getByRole("button", { name: /Connect Gmail with one click/i }),
+  ).toBeVisible({ timeout: 10_000 });
+});