Feat/add cr and cz macros

[paulQM]

Implements macros for CR and CZ gates on transmons (both flux tunable and fixed with fixed and tunable couplers)

Contains also fixes:

• Different formula for calculating blob distances in gef readout. Old formula did not work.
• Fix bug where if machine.set_all_fluxes got a qubit_pair, it would try call on the z line, not the coupler line.

[TheoLaudatQM]

Is there a reason for not using the framework that the IQCC team is using?
Especially with

@quam_dataclass
class TwoQubitGate(QuamComponent, ABC):
    
    extras: Dict[str, Any] = field(default_factory=dict)
    
    @property
    def transmon_pair(self):
        from ..transmon_pair import TransmonPair

        if isinstance(self.parent, TransmonPair):
            return self.parent
        elif hasattr(self.parent, "parent") and isinstance(self.parent.parent, TransmonPair):
            return self.parent.parent
        else:
            raise AttributeError("TwoQubitGate is not attached to a QubitPair. 2Q_gate: {self}")

    @property
    def qubit_control(self):
        return self.transmon_pair.qubit_control

    @property
    def qubit_target(self):
        return self.transmon_pair.qubit_target
    
    @property
    def coupler(self):
        return self.transmon_pair.coupler    

    def __call__(self):
        self.execute()


@quam_dataclass
class CZGate(TwoQubitGate):
    """CZ Operation for a qubit pair"""

[soonqm]

The implementation here seems to be more general and can be attached to any qubit type. Any recommendation for when to extend the class and when to use macro?

[soonqm]

In terms of consistency with the other custom_gates, cross_resonance is also implemented as macro. We could refactor this, but what is your current thought? My thought right now is that macro works because the implementation depends on what user have and can choose which appropriate gate to attached rather than being pre-defined.

[TheoLaudatQM]

I recently discussed it with @nulinspiratie and his advice is to use the Gate macros for 1 and 2 qubit gates and keep using the standard methods for other functions such as reset, readout...

[HiroQM]

@TheoLaudatQM I'd prefer consistency and open for changes. Here the class inherits quam.components.macro.QubitPairMacro. The IQCC implementation inherits TwoQubitGate(QuamComponent, ABC). Which approach should we take here? @nulinspiratie

[nulinspiratie]

The apply method in this class seems too big. I would recommend splitting it up into several methods. For example, each cr_type should be its own method or function. Also, I would expect that many of the parameters in apply are actually gate parameters similar to zz_correction_phase

[HiroQM]

@nulinspiratie Refactored the macro and decomposed them to methods. There are many parameters but many of them are for the operations (pulses) of involved elements. Is there a better way to manage these?

The location of the file was moved to: custom_gates/fixed_transmon_pair/two_qubit_gates.py following the changes in the flux tunable one.