fix: implement retry logic with ETag synchronization for Tidal playlist modifications and add test script

app.py

@@ -256,8 +256,9 @@ with tab_my:
                         st.session_state[tracks_key] = tracks
                         if err:
                             st.session_state[f"tracks_err_{pid}"] = err
-                        st.rerun()
-                else:
+                        cached_tracks = tracks
+
+                if cached_tracks is not None:
                     err = st.session_state.get(f"tracks_err_{pid}")
                     if err:
                         st.warning(err)
@@ -274,7 +275,7 @@ with tab_my:
                         st.dataframe(
                             pd.DataFrame(rows),
                             hide_index=True,
-                            use_container_width=True,
+                            width="stretch",
                             height=min(40 + len(rows) * 35, 300),
                             column_config={
                                 "":       st.column_config.TextColumn("", width="small"),
@@ -400,7 +401,7 @@ with tab_nf:
             for a, t in items
         ]
         if nf_rows:
-            st.dataframe(pd.DataFrame(nf_rows), hide_index=True, use_container_width=True,
+            st.dataframe(pd.DataFrame(nf_rows), hide_index=True, width="stretch",
                          height=min(80 + len(nf_rows) * 35, 500))
         else:
             st.info("No entries for this filter.")