fix: support qdrant-only vector maintenance

harness/tht/adapters/vector/thoth_http.py

@@ -2,6 +2,11 @@
 
 import re
 
+from tht.adapters.vector.pgvector import (
+    _collection,
+    _validate_collection_kinds,
+    _validate_known_kinds,
+)
 from tht.ports.vector import (
     VectorCapabilities,
     VectorHealth,
@@ -14,11 +19,6 @@ from tht.ports.vector import (
 )
 from tht.vectorstore.rest_client import VectorRestClient, VectorRestError
 from tht.vectorstore.store import hit_from_metadata
-from tht.adapters.vector.pgvector import (
-    _collection,
-    _validate_collection_kinds,
-    _validate_known_kinds,
-)
 
 
 def _merge(hits: list[VectorHit], limit: int) -> list[VectorHit]:
@@ -85,7 +85,7 @@ class ThothHttpVectorStore:
             return None, None, []
         try:
             return True, None, client.list_tables()
-        except Exception as exc:
+        except (RuntimeError, VectorRestError) as exc:
             return False, str(exc), []
 
     def search(
@@ -155,6 +155,14 @@ class ThothHttpVectorStore:
         except VectorRestError as exc:
             raise VectorStoreError(str(exc)) from exc
 
+    def delete_kinds(self, collection: str, kinds: list[str]) -> int:
+        _collection("vectors", collection)
+        _validate_collection_kinds(collection, kinds)
+        try:
+            return self._require_writer().delete_kinds(collection, kinds)
+        except VectorRestError as exc:
+            raise VectorStoreError(str(exc)) from exc
+
     def delete_generation(self, collection: str, generation: str, workspace_id: str) -> int:
         if collection != "evidence" or re.fullmatch(r"gen:[0-9a-f]{32}", generation) is None:
             raise VectorStoreError("Only exact Evidence generations may be deleted")