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_conversation_atomicity.py

@@ -0,0 +1,96 @@
+"""Crash-safety of ConversationStore's shrink rewrite (write-side atomicity).
+
+`save()` appends new messages on the common path, but when a turn *reduces* the message
+count (context compaction / summarization) it rewrites the whole ``.jsonl``. That rewrite
+must be atomic: a crash partway through must not truncate or erase the existing history —
+the most valuable data the app holds.
+
+This is the write-side complement to read-side corrupt-line tolerance: prevent the
+truncated file rather than cope with one after the fact.
+"""
+
+from __future__ import annotations
+
+import os
+
+import pytest
+
+from coworker.conversations import ConversationStore
+from coworker.sessions import SessionRecord
+
+
+def _rec(sid: str, n: int) -> SessionRecord:
+    return SessionRecord(
+        session_id=sid,
+        workspace="/w",
+        model="m",
+        mode="interactive",
+        messages=[{"role": "user", "content": f"msg-{i}"} for i in range(n)],
+    )
+
+
+def test_shrink_rewrite_preserves_history_when_write_crashes(tmp_path, monkeypatch):
+    store = ConversationStore(tmp_path)
+    sid = "sess1"
+
+    # Persist a 5-message history via the append path.
+    store.save(_rec(sid, 5))
+    assert len(store.load(sid).messages) == 5
+
+    # Force a crash partway through the shrink rewrite (5 -> 2): the write fails after the
+    # first line. A non-atomic in-place open(..., "w") truncates the real file at open() and
+    # the crash then erases the history; an atomic tmp-then-replace leaves the original
+    # untouched because the swap never happens.
+    import coworker.conversations as conv
+
+    real_open = open
+    writes = {"n": 0}
+
+    class _CrashingFile:
+        def __init__(self, fh):
+            self._fh = fh
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, *exc):
+            self._fh.close()
+            return False
+
+        def write(self, s):
+            writes["n"] += 1
+            if writes["n"] >= 2:
+                raise OSError("simulated crash mid-write")
+            return self._fh.write(s)
+
+    def crashing_open(file, mode="r", *args, **kwargs):
+        fh = real_open(file, mode, *args, **kwargs)
+        if "w" in mode and os.path.basename(str(file)).startswith(sid):
+            return _CrashingFile(fh)
+        return fh
+
+    monkeypatch.setattr(conv, "open", crashing_open, raising=False)
+
+    with pytest.raises(OSError):
+        store.save(_rec(sid, 2))
+
+    monkeypatch.undo()
+
+    # The interrupted shrink must not have destroyed the existing history.
+    assert len(store.load(sid).messages) == 5
+
+
+def test_shrink_rewrite_persists_reduced_history(tmp_path):
+    """The (non-crash) shrink path still rewrites the log to exactly the reduced set."""
+    store = ConversationStore(tmp_path)
+    sid = "sess2"
+
+    store.save(_rec(sid, 5))
+    assert len(store.load(sid).messages) == 5
+
+    store.save(_rec(sid, 3))  # shrink 5 -> 3
+    reloaded = store.load(sid)
+    assert [m["content"] for m in reloaded.messages] == ["msg-0", "msg-1", "msg-2"]
+
+    # No leftover temp file next to the conversation log.
+    assert not (tmp_path / "conversations" / f"{sid}.tmp").exists()