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

tests/test_mangled_tool_calls.py

@@ -0,0 +1,110 @@
+"""Mangled tool calls (`{"_raw": …}` fallback args) get a real diagnosis, not execution.
+
+The field failure (2026-08-15, report-page generation): a large write_file call blew the
+output-token limit, the truncated JSON became `{"_raw": …}`, and the tool's bare
+parameter error sent the model into a "wrong parameter" retry loop. Worse, each stored
+`_raw` call read as a worked example — after a few, the model began emitting `_raw` as
+if it were a real parameter, and every replay re-sent thousands of junk tokens.
+"""
+
+from __future__ import annotations
+
+import json
+
+import pytest
+
+from coworker.engine import EventType, TurnEngine, _MANGLED_PREVIEW_CHARS
+from coworker.permissions import Mode, PermissionEngine
+from coworker.providers import AssistantTurn, ModelCapabilities, ProviderClient, ToolCall
+from coworker.tools import ToolRegistry
+
+
+class MangledProvider(ProviderClient):
+    """One turn with unparseable write_file args, then a plain reply."""
+
+    def __init__(self, finish_reason: str, raw: str = "x" * 5000):
+        self.calls = 0
+        self.finish_reason = finish_reason
+        self.raw = raw
+
+    def complete(self, *, model, messages, tools=None, **settings):
+        self.calls += 1
+        if self.calls == 1:
+            return AssistantTurn(
+                text="",
+                tool_calls=[
+                    ToolCall(id="t1", name="write_file", arguments={"_raw": self.raw})
+                ],
+                finish_reason=self.finish_reason,
+            )
+        return AssistantTurn(text="done", tool_calls=[])
+
+    def capabilities(self, model):
+        return ModelCapabilities(tools=True)
+
+
+def _engine(tmp_path, provider) -> TurnEngine:
+    return TurnEngine(
+        provider=provider,
+        registry=ToolRegistry(),
+        permissions=PermissionEngine(workspace_root=tmp_path, mode=Mode.INTERACTIVE),
+        model="m",
+    )
+
+
+async def _run(engine) -> list:
+    return [e async for e in engine.run("build the report")]
+
+
+def _last_tool_message(engine) -> str:
+    return str([m for m in engine.messages if m.get("role") == "tool"][-1]["content"])
+
+
+@pytest.mark.asyncio
+async def test_truncated_call_is_answered_with_the_truncation_diagnosis(tmp_path):
+    """finish_reason "length" + unparseable args = the call was cut off. The model's cure
+    is smaller pieces — the error must say so instead of a bare parameter complaint."""
+    engine = _engine(tmp_path, MangledProvider("length"))
+    events = await _run(engine)
+
+    finished = [e for e in events if e.type is EventType.TOOL_FINISHED]
+    assert finished[0].data["status"] == "error"
+    body = _last_tool_message(engine)
+    assert "output-token limit" in body
+    assert "smaller pieces" in body
+    # The turn continues — no retry loop, the model answers after the diagnosis.
+    assert [e for e in events if e.type is EventType.TURN_END]
+
+
+@pytest.mark.asyncio
+async def test_plain_bad_json_is_answered_with_the_parameter_diagnosis(tmp_path):
+    """No truncation → the model wrote bad JSON (or imitated `_raw`). Tell it `_raw` is
+    not a parameter and to re-issue with the declared ones."""
+    engine = _engine(tmp_path, MangledProvider("stop"))
+    await _run(engine)
+    body = _last_tool_message(engine)
+    assert "_raw" in body and "not a parameter" in body
+    assert "declared parameters" in body
+
+
+@pytest.mark.asyncio
+async def test_raw_junk_is_shrunk_before_it_enters_history(tmp_path):
+    """The unparsed text must not be replayed at full size: it costs tokens every turn
+    and teaches the model that `_raw` is a shape to imitate."""
+    engine = _engine(tmp_path, MangledProvider("length", raw="y" * 5000))
+    await _run(engine)
+
+    assistant = [m for m in engine.messages if m.get("role") == "assistant" and m.get("tool_calls")][0]
+    stored = json.loads(assistant["tool_calls"][0]["function"]["arguments"])
+    assert len(stored["_raw"]) < _MANGLED_PREVIEW_CHARS + 100
+    assert "truncated in history" in stored["_raw"]
+
+
+@pytest.mark.asyncio
+async def test_short_raw_args_are_kept_verbatim(tmp_path):
+    """Below the preview cap there is nothing to shrink — storage stays faithful."""
+    engine = _engine(tmp_path, MangledProvider("stop", raw='{"path": "repo'))
+    await _run(engine)
+    assistant = [m for m in engine.messages if m.get("role") == "assistant" and m.get("tool_calls")][0]
+    stored = json.loads(assistant["tool_calls"][0]["function"]["arguments"])
+    assert stored == {"_raw": '{"path": "repo'}