fix: use share paths, drop additional from list_dir, remove debug logging

Root cause: DSM expects share paths (/dev) not volume paths (/volume1/dev).
The 408 errors were triggered by any additional field on the wrong path format.

- list_shares: use share["path"] directly (e.g. /dev), drop real_path from
  additional — only volume_status remains
- list_dir: remove additional parameter entirely; table now shows name + type
  (isdir is returned by default); update docstring to show share path examples
- client.py: remove diagnostic REQUEST and RAW ERROR stderr logging
- tests: update assertions to match share paths and two-column table output

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_tools_filestation.py

@@ -79,7 +79,8 @@ async def test_list_shares_success(config: AppConfig) -> None:
     result = await tools["list_shares"]()
 
     assert "data" in result
-    assert "/volume1/data" in result
+    assert "/data" in result          # share path, not volume path
+    assert "/volume1/data" not in result
     assert "photos" in result
     assert "2 share(s) found" in result
     # Check usage percentage appears
@@ -120,33 +121,21 @@ async def test_list_shares_dsm_error(config: AppConfig) -> None:
 
 @pytest.mark.asyncio
 async def test_list_dir_success(config: AppConfig) -> None:
-    """list_dir returns a formatted table with files and directories."""
+    """list_dir returns a formatted table with name and type columns."""
     client = MagicMock()
     client.request = AsyncMock(
         return_value={
             "total": 3,
             "files": [
-                {
-                    "name": "documents",
-                    "isdir": True,
-                    "additional": {"size": None, "time": {"mtime": 1700000000}},
-                },
-                {
-                    "name": "photo.jpg",
-                    "isdir": False,
-                    "additional": {"size": 2_500_000, "time": {"mtime": 1700100000}},
-                },
-                {
-                    "name": "readme.txt",
-                    "isdir": False,
-                    "additional": {"size": 1024, "time": {"mtime": 1700200000}},
-                },
+                {"name": "documents", "isdir": True},
+                {"name": "photo.jpg", "isdir": False},
+                {"name": "readme.txt", "isdir": False},
             ],
         }
     )
 
     tools = _make_mcp_and_tools(config, client)
-    result = await tools["list_dir"](path="/volume1/data")
+    result = await tools["list_dir"](path="/dev")
 
     assert "documents" in result
     assert "photo.jpg" in result
@@ -164,11 +153,7 @@ async def test_list_dir_pagination(config: AppConfig) -> None:
         return_value={
             "total": 200,
             "files": [
-                {
-                    "name": f"file{i}.txt",
-                    "isdir": False,
-                    "additional": {"size": 100, "time": {"mtime": 1700000000 + i}},
-                }
+                {"name": f"file{i}.txt", "isdir": False}
                 for i in range(100)
             ],
         }