Episode highlights per series: tag by lane, group on Episodes page, move to Finished Book when series ends; v2.9.1

- Highlights get a Series field (Lane A / Lane B / General); legacy highlights count as Lane A
- Episodes page groups highlights under each series' title
- Ending a series (scheduled or manual) moves only that series' highlights onto its Finished Book page; other lane and General stay
- Archived highlights keep working: detail pages, sitemap, scripture index and search include them

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

package.json

@@ -1,7 +1,7 @@
 {
   "name": "siteforge",
   "private": true,
-  "version": "2.9.0",
+  "version": "2.9.1",
   "type": "module",
   "scripts": {
     "dev": "vite",