fix: pre-road audit (Phase 30) — upload-loop OSError, stats lock scope, server int guards

modules/app_sql.py

@@ -504,6 +504,9 @@ def get_overview_stats():
         dtc_row = conn.execute(
             "SELECT COUNT(*) FROM dtc WHERE IS_SET = 1"
         ).fetchone()
+        cumul = conn.execute(
+            "SELECT COALESCE(SUM(DISTANCE_KM), 0) FROM trips"
+        ).fetchone()
     from modules import app_video as _av
     try:
         video_count = sum(1 for _ in _av.list_local_videos().get("files", []))
@@ -511,7 +514,6 @@ def get_overview_stats():
         video_count = 0
     from modules import app_settings
     base = app_settings._number_value("odometer_baseline", float, 0)
-    cumul = conn.execute("SELECT COALESCE(SUM(DISTANCE_KM), 0) FROM trips").fetchone()
     computed = base + (cumul[0] if cumul else 0)
     return {
         "trip_count": row[0],