fix(evidence): validate ownership before all searches

harness/tests/test_corpus_pipeline.py

@@ -257,7 +257,10 @@ def test_active_searcher_splits_default_and_mixed_kinds_before_global_limit(tmp_
     from tht.search.evidence import ActiveEvidenceSearcher
 
     store = CorpusStore(tmp_path / "corpus")
-    generation = store.stage(CorpusManifest(), {}, generation="gen:" + "a" * 32)
+    generation = store.stage(
+        CorpusManifest(metadata={"workspace_id": "default"}), {},
+        generation="gen:" + "a" * 32,
+    )
     store.publish(generation)
     calls = []
 
@@ -368,7 +371,8 @@ def test_gc_rejects_workspace_mismatch_without_deleting(tmp_path):
     assert wrong.store.list_generations() == generations
 
 
-def test_active_search_rejects_workspace_mismatch_before_delegate(tmp_path):
+@pytest.mark.parametrize("kinds", [None, ["evidence", "memory"], ["memory"]])
+def test_active_search_rejects_workspace_mismatch_before_delegate(tmp_path, kinds):
     from tht.search.evidence import ActiveEvidenceSearcher, CorpusWorkspaceMismatchError
 
     vectors = Vectors()
@@ -386,7 +390,33 @@ def test_active_search_rejects_workspace_mismatch_before_delegate(tmp_path):
     with pytest.raises(CorpusWorkspaceMismatchError, match="different workspace"):
         ActiveEvidenceSearcher(
             owner.store, Delegate(), expected_workspace_id="workspace-b",
-        ).search([1.0], kinds=["evidence"])
+        ).search([1.0], kinds=kinds)
+
+
+def test_unscoped_active_manifest_is_never_adopted_by_direct_run_or_gc(tmp_path):
+    store = CorpusStore(tmp_path / "corpus")
+    generation = store.stage(CorpusManifest(), {})
+    store.publish(generation)
+
+    class ForbiddenSource:
+        def discover(self):
+            raise AssertionError("invalid corpus reached source discovery")
+
+    class ForbiddenVectors:
+        def __getattr__(self, name):
+            raise AssertionError(f"invalid corpus reached vector operation {name}")
+
+    candidate = CorpusPipeline(
+        store=store, sources=[ForbiddenSource()], embedder=Embedder(),
+        vector_store=ForbiddenVectors(), embedding_model="model", embedding_dimensions=3,
+        chunk_policy=ChunkPolicy(version="chunk-v1", max_chars=100),
+        pipeline_version="evidence-v1",
+    )
+    with pytest.raises(PipelineError, match="missing or invalid"):
+        candidate.run()
+    with pytest.raises(PipelineError, match="missing or invalid"):
+        candidate.gc(workspace_root=tmp_path)
+    assert store.active_generation() == generation
 
 
 def test_unchanged_documents_skip_acquire_normalize_chunk_and_embed(tmp_path):