v0.12.0

Added

• Two new Insights Milestones: total workouts logged and total calories burned. Lifetime
  counterparts to the existing "years rowing" and "hours on the erg" cards, same "always-true
  fun fact" treatment (gated only on having enough history, no significance test). Concept2 has
  no rest-period calorie figure anywhere in its API, so total calories is a plain sum — no
  work/rest split to worry about there, unlike distance and time.
• New rest_time_seconds column, mirroring rest_distance_meters (0.11.0). Concept2 tracks
  rest-interval time separately from work-interval time the same way it does distance —
  Workout.total_time_seconds (work + rest) now feeds the "hours on the erg" milestone, so a
  session with light rowing between intervals counts all of it as real time spent rowing. Pace
  and PBs stay on work-only time_seconds, untouched, same reasoning as the meters fix.
• backfill_rest_meters.py now backfills both rest_distance_meters and rest_time_seconds in
  the same live-API pass.