#8202 plot_bloch_vector optional parameter & allowing initialize state in visualize_transition & minor issue

[poig]

Summary

Closes #8202
adding optional argument allowed for matplotlib.patches.FancyArrowPatch to plot_bloch_vector
Closes #8194
document qiskit.extensions.StatePreparation to qiskit.circuit.library.data_preparation.StatePreparation
Closes #8206
allowing initialize state in visualize_transition.

from qiskit import QuantumCircuit
import numpy as np
from qiskit.visualization import plot_bloch_multivector, visualize_transition
from qiskit.quantum_info import Statevector, random_statevector
ran_sv = random_statevector(2)
qc = QuantumCircuit(1)
qc.initialize(ran_sv.data,0)
qc.h(0)
qc.x(0)
qc.ry(np.pi/2,0)
display(qc.draw('mpl'))

plot_bloch_multivector(qc,ls="dotted")

visualize_transition(qc,trace=True)

Details and comments

not sure if doing everything correctly
do visualize_transition need a test?

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[coveralls]

Pull Request Test Coverage Report for Build 2533203377

• 10 of 24 (41.67%) changed or added relevant lines in 3 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 84.267%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
qiskit/visualization/bloch.py	7	8	87.5%
qiskit/visualization/transition_visualization.py	0	13	0.0%

Files with Coverage Reduction	New Missed Lines	%
qiskit/visualization/transition_visualization.py	1	10.95%

Totals
Change from base Build 2529092568:	-0.01%
Covered Lines:	54898
Relevant Lines:	65148

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💛 - Coveralls

[javabster]

Hi @poig thanks for your contribution and sorry for the slow review on this PR, I think because it is attempting to address a few different issues it fell through the cracks and it probably would have been better to split this into 2 PRs (one for the documentation fix and another for the visualisation feature).

Generally this is looking good, but to move forward I think the visualize_transition piece should be removed from this PR, as the visualise_transition() function is likely to be removed at some point (see #9355)