Update __init__.py

Author: NeuralBlitz

__init__.py

@@ -1,8 +1,16 @@
 # quantum_sim/__init__.py
 
-# This file marks 'quantum_sim' as a Python package.
-# It can also be used to selectively import core components for easier access.
-# from .core.circuit import QuantumCircuit
-# from .core.parameter import Parameter
-# from .gates.single_qubit_gates import Hadamard
-# from .backends.numpy_backend import NumpyBackend
+"""
+Quantum Simulation Engine
+A high-performance density matrix simulator for NISQ-era algorithms.
+"""
+
+from .core.circuit import QuantumCircuit
+from .core.parameter import Parameter
+from .backend.numpy_backend import NumpyBackend
+
+__all__ = [
+    "QuantumCircuit",
+    "Parameter",
+    "NumpyBackend",
+]