refactor(trajectory): fix code quality issues in centroid diagnostics

explorer_helpers.py

@@ -254,17 +254,18 @@ def compute_party_centroids(
     - party_centroids: mapping party -> list of (x,y) tuples of length len(windows).
       Entries without MPs are (np.nan, np.nan).
     - metadata: dict with keys 'per_party_counts', 'total_windows', 'parties',
-      'input_windows', 'input_party_map_entries', 'windows_processed',
+      'windows_with_data_count', 'input_party_map_entries', 'windows_processed',
-      'parties_with_positions', 'parties_all_nan', 'name_mismatch_samples'
+      'parties_with_positions', 'parties_all_nan'
     """
     # Initialize diagnostics metadata
     metadata = {
-        "input_windows": len(positions_by_window) if positions_by_window else 0,
+        "windows_with_data_count": len(positions_by_window)
+        if positions_by_window
+        else 0,
         "input_party_map_entries": len(party_map) if party_map else 0,
         "windows_processed": 0,
         "parties_with_positions": set(),
         "parties_all_nan": [],
-        "name_mismatch_samples": [],
         "per_party_counts": {},
         "total_windows": len(windows),
         "parties": [],