test: allow duplicate IDs across component kinds

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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: marcelsafin

tests/contract/test_manifest_schema.py

@@ -141,6 +141,15 @@ def test_duplicate_component_in_same_kind_is_rejected():
     )
 
 
+def test_same_component_id_in_different_kinds_is_allowed():
+    data = valid_manifest_dict()
+    data["provides"]["steps"].append({"id": "ext-a"})
+
+    errors = BundleManifest.from_dict(data).structural_errors()
+
+    assert not any("duplicate" in error.lower() for error in errors)
+
+
 def test_string_tags_rejected_not_split_per_character():
     # A bare string would otherwise be iterated character-by-character; the
     # schema requires a list of strings.