feat(backend): add CycloneParseError and CycloneValidationError

backend/tests/test_exceptions.py

@@ -0,0 +1,21 @@
+import pytest
+from cyclone.parsers.exceptions import CycloneParseError, CycloneValidationError
+
+
+def test_parse_error_carries_segment_index():
+    err = CycloneParseError("bad CLM", segment_index=42)
+    assert err.segment_index == 42
+    assert "bad CLM" in str(err)
+    assert "segment 42" in str(err)
+
+
+def test_validation_error_carries_rule_id():
+    err = CycloneValidationError("NPI bad", rule_id="R020_npi_format", claim_id="C1")
+    assert err.rule_id == "R020_npi_format"
+    assert err.claim_id == "C1"
+    assert "[R020_npi_format]" in str(err)
+
+
+def test_parse_error_inherits_from_exception():
+    assert issubclass(CycloneParseError, Exception)
+    assert issubclass(CycloneValidationError, Exception)