[BUG] RotationComposer does not have support for integral mutliples of pi/8 rotations

[isolatedinformation]

Issue Description

As suggested in the discussion of PR #269, LLOPs only has support for [pi/2, +/- pi/4 , +/- pi/8 ]!

lattice-surgery-compiler/src/lsqecc/logical_lattice_ops/logical_lattice_ops.py

Lines 159 to 173 in d59f447

	if r.rotation_amount == Fraction(1, 2):
	return self.pi_over_two(r.get_ops_map(), r.get_condition())
	elif r.rotation_amount == Fraction(1, 4):
	return self.add_pi_over_four(r.get_ops_map(), False, r.get_condition())
	elif r.rotation_amount == Fraction(-1, 4):
	return self.add_pi_over_four(r.get_ops_map(), True, r.get_condition())
	elif r.rotation_amount == Fraction(1, 8):
	return self.add_pi_over_eight(r.get_ops_map(), False, r.get_condition())
	elif r.rotation_amount == Fraction(-1, 8):
	return self.add_pi_over_eight(r.get_ops_map(), True, r.get_condition())
	else:
	raise Exception(
	"Unsupported pauli rotation angle pi*%d/%d"
	% (r.rotation_amount.numerator, r.rotation_amount.denominator)
	)

To fully take leverage of the compression from this PR, LLOPs should have support for all integral multiples of pi/8

How to Reproduce

If possible, please provide us with the steps that lead to the behavior that you are seeing, and include the snippet of the code that generates the error as well as the error message from python below.

Code Snippet

from fractions import Fraction
from lsqecc.pauli_rotations import PauliOpCircuit, PauliRotation, PauliOperator
import lsqecc.logical_lattice_ops.logical_lattice_ops as llops

Z = PauliOperator.Z

circ = PauliOpCircuit(1)
circ.add_pauli_block(PauliRotation.from_list([Z], rotation=Fraction(3, 8)))
print(circ)

log_comp = llops.LogicalLatticeComputation(circ)

Error Output

Traceback (most recent call last):
  File "/home/varunseshadri/projects/lattice-surgery/lattice-surgery-compiler/debug/debug_non_standard_rotation_composer.py", line 15, in <module>
    log_comp = llops.LogicalLatticeComputation(circ)
  File "/home/varunseshadri/projects/lattice-surgery/lattice-surgery-compiler/src/lsqecc/logical_lattice_ops/logical_lattice_ops.py", line 100, in __init__
    self._load_circuit()
  File "/home/varunseshadri/projects/lattice-surgery/lattice-surgery-compiler/src/lsqecc/logical_lattice_ops/logical_lattice_ops.py", line 121, in _load_circuit
    reversed(rotations_composer.expand_rotation(current_op))
  File "/home/varunseshadri/projects/lattice-surgery/lattice-surgery-compiler/src/lsqecc/logical_lattice_ops/logical_lattice_ops.py", line 170, in expand_rotation
    raise Exception(
Exception: Unsupported pauli rotation angle pi*3/8

Environment Context

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