Address code review: remove unused ValidationError class and redundant filter

Co-authored-by: toby-coleman <13170610+toby-coleman@users.noreply.github.com>

Author: Copilot

plugboard-schemas/plugboard_schemas/__init__.py

@@ -11,7 +11,6 @@
 from ._common import PlugboardBaseModel
 from ._graph import simple_cycles
 from ._validation import (
-    ValidationError,
     validate_all_inputs_connected,
     validate_input_events,
     validate_no_unresolved_cycles,
@@ -92,7 +91,6 @@
     "TuneArgsDict",
     "TuneArgsSpec",
     "TuneSpec",
-    "ValidationError",
     "simple_cycles",
     "validate_all_inputs_connected",
     "validate_input_events",

plugboard-schemas/plugboard_schemas/_validation.py

@@ -19,12 +19,6 @@
     from .connector import ConnectorSpec
 
 
-class ValidationError(Exception):
-    """Raised when a process specification fails validation."""
-
-    pass
-
-
 def _build_component_graph(
     connectors: list[ConnectorSpec],
 ) -> dict[str, set[str]]:
@@ -62,13 +56,12 @@ def _get_edges_in_cycle(
         List of connector specs that are part of the cycle.
     """
     cycle_edges: list[ConnectorSpec] = []
-    cycle_set = set(cycle)
     for i, node in enumerate(cycle):
         next_node = cycle[(i + 1) % len(cycle)]
         for conn in connectors:
             if conn.source.entity == node and conn.target.entity == next_node:
                 cycle_edges.append(conn)
-    return [c for c in cycle_edges if c.source.entity in cycle_set and c.target.entity in cycle_set]
+    return cycle_edges
 
 
 def validate_all_inputs_connected(