PR: Added gate Alias and minor fix in MCY gate

[Giacomo-Antonioli]

Add Gate Wrapper Methods and Comprehensive Tests

Overview

This PR implements wrapper methods for all gate types in the QCircuit class and adds comprehensive tests to ensure they work correctly.

What's New

1. Gate Wrapper Methods

Added convenient wrapper methods to QCircuit for all supported gate types:

• Single-qubit gates: H(), X(), Y(), Z(), RX(), RY(), RZ(), Phase(), U2(), U3()
• Two-qubit gates: CNOT(), CZ(), CY(), SWAP(), iSWAP(), CPhase(), CRX(), CRY(), CRZ(), CU2(), CU3()
• Multi-controlled gates: MCX(), MCY(), MCZ(), MCRX(), MCRY(), MCRZ(), MCMG()
• Matrix gates: MG(), MCMG()
• Phase gates: Phase45(), Phase90(), T(), S()
• Two-qubit rotations: RXX(), RYY(), RZZ()

2. Comprehensive Test Suite

Created extensive tests that verify:

• Wrapper vs Full Class Equivalence: Each wrapper method creates gates identical to their full class counterparts
• Parameter Accuracy: All gate parameters (angles, control states, matrices) are correctly set
• Floating-Point Robustness: Tolerance-based comparisons handle numerical precision issues
• Circuit Building: Multi-gate circuits and method chaining work correctly

3. Bug Fix

• MCY Equals Method: Fixed a typo in the MCY gate's equals function that was preventing proper gate comparison

Key Features

Convenient API

% Before
circuit.push_back(qclab.qgates.Hadamard(0));

% After  
circuit.H(0);