style: fix import ordering flagged by ruff I001

After the ``hypergraph._types`` module removal, two import blocks
needed re-sorting: ``pylinkage._types`` sorts before
``pylinkage.assur.*``, and ``from .sim_conversion`` belongs after the
sibling ``serialization`` block.

Author: HugoFara

src/pylinkage/hypergraph/__init__.py

@@ -61,7 +61,6 @@
 # Hierarchical composition
 from .hierarchy import ComponentInstance, Connection, HierarchicalLinkage
 from .mechanism_conversion import from_mechanism, to_mechanism
-from .sim_conversion import from_sim_linkage
 
 # Serialization
 from .serialization import (
@@ -74,6 +73,7 @@
     hierarchical_to_dict,
     hierarchical_to_json,
 )
+from .sim_conversion import from_sim_linkage
 
 __all__ = [
     # Types

tests/assur/test_hypergraph_conversion.py

@@ -2,12 +2,12 @@
 
 import unittest
 
+from pylinkage._types import JointType as HyperJointType
+from pylinkage._types import NodeRole as HyperNodeRole
 from pylinkage.assur.graph import Edge as AssurEdge
 from pylinkage.assur.graph import JointType, LinkageGraph, NodeRole
 from pylinkage.assur.graph import Node as AssurNode
 from pylinkage.assur.hypergraph_conversion import from_hypergraph, to_hypergraph
-from pylinkage._types import JointType as HyperJointType
-from pylinkage._types import NodeRole as HyperNodeRole
 from pylinkage.hypergraph.core import Edge as HyperEdge
 from pylinkage.hypergraph.core import Node as HyperNode
 from pylinkage.hypergraph.graph import HypergraphLinkage