Fix vector search parameter ordering for pgvector

%s placeholders in SQL are positional — SELECT score param must come
before WHERE conditions in the params list, not after.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Knowledgebase/server.py

@@ -442,17 +442,23 @@ def search(
                     vec_params2.append(min_importance)
 
                 vec_where = " AND ".join(vec_conditions)
+                qv = np.array(query_emb)
+                # Pořadí %s musí odpovídat pořadí v SQL:
+                # 1. WHERE podmínky (vec_params2)
+                # 2. SELECT score: embedding <=> %s
+                # 3. ORDER BY: embedding <=> %s
+                # 4. LIMIT %s
                 vec_rows = conn.execute(
                     f"""
                     SELECT id, mem_type, title, content, summary, tags,
                            project, source, session_id, importance, created_at,
-                           1 - (embedding <=> %s::vector) AS score
+                           1 - (embedding <=> %s) AS score
                     FROM kb_memories
                     WHERE {vec_where}
-                    ORDER BY embedding <=> %s::vector
+                    ORDER BY embedding <=> %s
                     LIMIT %s
                     """,
-                    [np.array(query_emb), np.array(query_emb)] + vec_params2 + [limit],
+                    [qv] + vec_params2 + [qv, limit],
                 ).fetchall()
 
                 for r in vec_rows: