Expand admin dashboard with trends, health, study and email insights; v2.8.0

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

server.js

@@ -51,6 +51,7 @@ import { register as registerAdminAuth } from './server/routes/admin-auth.js'
 import { register as registerAdminContent, runScheduledSeriesTransition } from './server/routes/admin-content.js'
 import { register as registerAdminAssets } from './server/routes/admin-assets.js'
 import { register as registerAdminBackup } from './server/routes/admin-backup.js'
+import { register as registerAdminDashboard } from './server/routes/admin-dashboard.js'
 import { register as registerStudyAuth } from './server/routes/study-auth.js'
 import { register as registerStudyData } from './server/routes/study-data.js'
 import { register as registerStudyAccount } from './server/routes/study-account.js'
@@ -104,6 +105,7 @@ registerAdminAuth(app)
 registerAdminContent(app)
 registerAdminAssets(app)
 registerAdminBackup(app)
+registerAdminDashboard(app)
 registerStudyAuth(app)
 registerStudyData(app)
 registerStudyAccount(app)