feat: add minimal main function and passing test case

Co-authored-by: aider (openrouter/deepseek/deepseek-v4-pro) <aider@aider.chat>

src/main.py

@@ -0,0 +1,3 @@
+def main():
+    """Entry point for the application."""
+    pass

tests/test_main.py

@@ -0,0 +1,3 @@
+def test_main():
+    """Minimal test that always passes."""
+    assert True