summary: Add time restriction to comments_count subquery
summary: Add time restriction to comments_count subquery

We don't need to count all the comments: since we are only interested
in recent posts, it's fine to only count the recent comments (because
comments are always created after respective posts, obviously).

Added to subquery:
  WHERE created_at > (current_date - ${days} * interval '1 day')

Subquery performance: 2800 ms -> 120 ms

Full query performance: 8100 ms -> 2300 ms

FreeFeed/freefeed-server,FreeFeed/freefeed-server