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/reasoning.spec.ts

@@ -0,0 +1,31 @@
+// Model-layer roadmap item 4 (2026-07-22): reasoning traces. Live turn shows a quiet
+// pulsing "Thinking…" disclosure that streams the trace; once the message finalizes the
+// trace folds into a collapsed "Thought process" disclosure on the answer bubble.
+import { expect } from "@playwright/test";
+import { test } from "./fixtures";
+
+test("thinking streams live, then persists as a collapsed disclosure on the answer", async ({
+  page,
+}) => {
+  await page.goto("/");
+  await page.getByText("Draft the launch note").first().click();
+  const box = page.getByPlaceholder(/Ask the coworker/);
+  await box.fill("think hard about this");
+  await box.press("Enter");
+
+  // Live phase: the Thinking… block is up while deltas tick in; expanding shows the trace.
+  await expect(page.getByText("Thinking…").first()).toBeVisible({ timeout: 10_000 });
+  await page.getByTestId("thinking-toggle").click();
+  await expect(page.getByTestId("thinking-body")).toContainText("Weighing options.");
+
+  // Finalized: the answer bubble carries a collapsed "Thought process" disclosure.
+  await expect(page.getByText("Decision made.").first()).toBeVisible({ timeout: 10_000 });
+  await expect(page.getByText("Thinking…")).toHaveCount(0);
+  const toggle = page.getByTestId("thinking-toggle");
+  await expect(toggle).toHaveText(/Thought process/);
+  await expect(page.getByTestId("thinking-body")).toHaveCount(0); // collapsed by default
+  await toggle.click();
+  await expect(page.getByTestId("thinking-body")).toContainText(
+    "Weighing options. Comparing tradeoffs. Settling it.",
+  );
+});