feat(series): run each round from the series page

Step 3 becomes a rounds table: pick drivers inline (copy from the
previous round, add a late entry), set qualifying rounds/finals/max
cars per heat per round, see the status, and create qualifying and
finals from there. Qualifying heats are now split evenly so nobody
drives alone.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "rc-racecore",
-  "version": "1.36.1",
+  "version": "1.37.0",
   "private": true,
   "description": "RC RaceCore live timing and race control with AMMC ingest and SQLite persistence",
   "engines": {