refactor: Improve compatibility shim for historical imports and enhance module loading

src/thechart/main.py

@@ -1,8 +1,38 @@
+from __future__ import annotations
+
 """Package proxy to the development entry module.
 
 This makes `thechart.main` importable while keeping the app in `src/main.py`.
 """
 
-from __future__ import annotations
+"""Compatibility shim for historical `from thechart import main` imports.
 
-from src.main import *  # noqa: F401,F403
+Delegates to the existing application entrypoint from common locations
+without forcing a hard dependency on the src layout.
+"""
+
+import importlib  # noqa: E402
+
+# Re-export run() and MedTrackerApp from the located main module
+try:
+    _mod = importlib.import_module("src.main")
+except Exception:
+    try:
+        _mod = importlib.import_module("main")
+    except Exception:  # Fallback to package dispatcher
+        from .__main__ import main as _entry_main  # type: ignore
+
+        def run() -> None:  # noqa: D401
+            """Run the application."""
+
+            _entry_main()
+
+        __all__ = ["run"]
+    else:
+        from main import *  # type: ignore  # noqa: F401,F403
+
+        __all__ = [name for name in dir() if not name.startswith("_")]
+else:
+    from src.main import *  # type: ignore  # noqa: F401,F403
+
+    __all__ = [name for name in dir() if not name.startswith("_")]