fix: route leaderboards rank by moving time not elapsed — top-10 route times and route completions list now use COALESCE(moving_time_s, duration_s) so mid-activity pauses don't inflate times (consistent with moving-time avg pace)

backend/app/api/activities.py

@@ -423,17 +423,21 @@ async def get_route_leaderboard(
     if not act.named_route_id:
         return None
 
+    # Rank by moving time (pauses excluded), falling back to elapsed for
+    # activities without it — consistent with avg pace being moving-time based.
+    effort_s = func.coalesce(Activity.moving_time_s, Activity.duration_s)
     rows = (await db.execute(
         select(
             Activity.id, Activity.name, Activity.start_time,
-            Activity.duration_s, Activity.distance_m, Activity.avg_heart_rate,
+            effort_s.label("duration_s"),
+            Activity.distance_m, Activity.avg_heart_rate,
         )
         .where(
             Activity.named_route_id == act.named_route_id,
             Activity.user_id == current_user.id,
             Activity.duration_s.isnot(None),
         )
-        .order_by(Activity.duration_s)
+        .order_by(effort_s)
     )).all()
     if not rows:
         return None