add top k button set default to 10

app.py

@@ -70,7 +70,7 @@ w_countries = pn.widgets.MultiSelect(name="Countries", options=country_opts)
 w_years = pn.widgets.MultiSelect(name="Years", options=year_opts)
 w_keyword = pn.widgets.TextInput(name="Keyword Search", placeholder="Search questions or answers with exact string matching")
 w_group = pn.widgets.Checkbox(name="Group by Question Text", value=False)
-w_topk = pn.widgets.Select(name="Top-K (semantic)", options=[5, 10, 20, 50, 100], value=50, disabled=True)
+w_topk = pn.widgets.Select(name="Top-K (semantic)", options=[5, 10, 20, 50, 100], value=10, disabled=True)
 
 w_semquery = pn.widgets.TextInput(name="Semantic Query", placeholder="LLM-powered semantic search")
 w_search_button = pn.widgets.Button(name="Search", button_type="primary")
@@ -187,7 +187,9 @@ sidebar = pn.Column(
     w_countries, w_years, w_keyword, w_group,
     pn.Spacer(height=20),
     "## 🧠 Semantic Search",
-    w_semquery, w_search_button,
+    w_semquery, 
+    w_topk,
+    w_search_button,
     pn.Spacer(height=20),
     w_clear_filters,
     width=300