Initial commit: Shelly Manager with Textual CLI, Streamlit UI, and comprehensive .gitignore

Shelly device management app with mDNS/subnet discovery, inventory,
configuration, and mass operations for Gen1/Gen2+ devices.

Includes .gitignore excluding runtime data (device DB, user config),
AI conversation history, build artifacts, and common Python/OS patterns.

tests/conftest.py

@@ -0,0 +1,32 @@
+"""Pytest fixtures."""
+
+from __future__ import annotations
+
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from shelly_manager.core.config import AppConfig
+
+
+@pytest.fixture
+def tmp_data_dir() -> Path:
+    with tempfile.TemporaryDirectory() as d:
+        yield Path(d)
+
+
+@pytest.fixture
+def app_config_sqlite(tmp_data_dir: Path) -> AppConfig:
+    return AppConfig(
+        storage_backend="sqlite",
+        sqlite_path=tmp_data_dir / "test.db",
+    )
+
+
+@pytest.fixture
+def app_config_markdown(tmp_data_dir: Path) -> AppConfig:
+    return AppConfig(
+        storage_backend="markdown",
+        markdown_dir=tmp_data_dir / "md",
+    )