feat: add get_info tool using SYNO.FileStation.List::getinfo

SYNO.FileStation.Stat is absent from this NAS's API registry.
SYNO.FileStation.List::getinfo returns identical data and is confirmed
working.

- tools/filestation.py: new get_info tool — accepts one or more
  comma-separated paths, calls getinfo with real_path/size/time/perm/
  owner/type additional fields, returns a 9-column table
- tests: 6 new tests covering single file, directory, multi-path,
  empty input, DSM error, and correct API method assertion
- SPEC.md: remove SYNO.FileStation.Stat from API table, rewrite get_info
  tool section to reference getinfo, update list_dir note
- CLAUDE.md: update Implemented Tools list

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

tests/test_tools_filestation.py

@@ -251,3 +251,165 @@ async def test_list_dir_dsm_error(config: AppConfig) -> None:
 
     assert result.startswith("Error:")
     assert "not found" in result.lower()
+
+
+# ──────────────────────────────────────────────────────────────────────────
+# get_info
+# ──────────────────────────────────────────────────────────────────────────
+
+
+@pytest.mark.asyncio
+async def test_get_info_single_file(config: AppConfig) -> None:
+    """get_info returns a table with metadata for a single file."""
+    client = MagicMock()
+    client.request = AsyncMock(
+        return_value={
+            "files": [
+                {
+                    "path": "/dev/notes.txt",
+                    "name": "notes.txt",
+                    "isdir": False,
+                    "additional": {
+                        "real_path": "/volume1/dev/notes.txt",
+                        "size": 1024,
+                        "time": {"mtime": 1700000000, "crtime": 1690000000},
+                        "owner": {"user": "marcus", "group": "users"},
+                        "perm": {"posix": 0o644},
+                    },
+                }
+            ]
+        }
+    )
+
+    tools = _make_mcp_and_tools(config, client)
+    result = await tools["get_info"](path="/dev/notes.txt")
+
+    assert "/dev/notes.txt" in result
+    assert "file" in result
+    assert "1 KB" in result or "1024 B" in result
+    assert "marcus" in result
+    assert "users" in result
+    assert "644" in result
+    assert "/volume1/dev/notes.txt" in result
+    assert "1 item(s)" in result
+
+
+@pytest.mark.asyncio
+async def test_get_info_directory(config: AppConfig) -> None:
+    """get_info shows '-' for size of a directory."""
+    client = MagicMock()
+    client.request = AsyncMock(
+        return_value={
+            "files": [
+                {
+                    "path": "/dev",
+                    "name": "dev",
+                    "isdir": True,
+                    "additional": {
+                        "real_path": "/volume1/dev",
+                        "size": 0,
+                        "time": {"mtime": 1700000000, "crtime": 1690000000},
+                        "owner": {"user": "marcus", "group": "users"},
+                        "perm": {"posix": 0o755},
+                    },
+                }
+            ]
+        }
+    )
+
+    tools = _make_mcp_and_tools(config, client)
+    result = await tools["get_info"](path="/dev")
+
+    assert "dir" in result
+    assert "755" in result
+    # Size for directory should be "-"
+    rows = [line for line in result.splitlines() if "/dev" in line and "|" in line]
+    assert rows, "expected a data row containing /dev"
+    size_col = rows[0].split("|")[3].strip()
+    assert size_col == "-"
+
+
+@pytest.mark.asyncio
+async def test_get_info_multiple_paths(config: AppConfig) -> None:
+    """get_info handles comma-separated paths and returns one row per item."""
+    client = MagicMock()
+    client.request = AsyncMock(
+        return_value={
+            "files": [
+                {
+                    "path": "/dev/a.txt",
+                    "name": "a.txt",
+                    "isdir": False,
+                    "additional": {
+                        "size": 100,
+                        "time": {"mtime": 1700000000, "crtime": 1690000000},
+                        "owner": {"user": "marcus", "group": "users"},
+                        "perm": {"posix": 0o644},
+                    },
+                },
+                {
+                    "path": "/data/b.txt",
+                    "name": "b.txt",
+                    "isdir": False,
+                    "additional": {
+                        "size": 200,
+                        "time": {"mtime": 1700000001, "crtime": 1690000001},
+                        "owner": {"user": "marcus", "group": "users"},
+                        "perm": {"posix": 0o644},
+                    },
+                },
+            ]
+        }
+    )
+
+    tools = _make_mcp_and_tools(config, client)
+    result = await tools["get_info"](path="/dev/a.txt,/data/b.txt")
+
+    assert "/dev/a.txt" in result
+    assert "/data/b.txt" in result
+    assert "2 item(s)" in result
+
+    # Verify the API received both paths as a comma-joined string
+    call_params = client.request.call_args[1]["params"]
+    assert call_params["path"] == "/dev/a.txt,/data/b.txt"
+
+
+@pytest.mark.asyncio
+async def test_get_info_empty_path(config: AppConfig) -> None:
+    """get_info returns Error: when path is empty."""
+    client = MagicMock()
+    client.request = AsyncMock()
+
+    tools = _make_mcp_and_tools(config, client)
+    result = await tools["get_info"](path="   ")
+
+    assert result.startswith("Error:")
+    client.request.assert_not_called()
+
+
+@pytest.mark.asyncio
+async def test_get_info_dsm_error(config: AppConfig) -> None:
+    """get_info returns Error: on SynologyError."""
+    client = MagicMock()
+    client.request = AsyncMock(side_effect=SynologyError("File or folder not found", code=1800))
+
+    tools = _make_mcp_and_tools(config, client)
+    result = await tools["get_info"](path="/dev/missing.txt")
+
+    assert result.startswith("Error:")
+    assert "not found" in result.lower()
+
+
+@pytest.mark.asyncio
+async def test_get_info_uses_getinfo_method(config: AppConfig) -> None:
+    """get_info calls SYNO.FileStation.List with method='getinfo'."""
+    client = MagicMock()
+    client.request = AsyncMock(return_value={"files": []})
+
+    tools = _make_mcp_and_tools(config, client)
+    await tools["get_info"](path="/dev/file.txt")
+
+    client.request.assert_called_once()
+    call_args = client.request.call_args
+    assert call_args[0][0] == "SYNO.FileStation.List"
+    assert call_args[0][1] == "getinfo"