feat(training+controls): interactive video pipeline, training blocks, control generator, CE libraries

Interactive Training Videos (CP-TRAIN):
- DB migration 022: training_checkpoints + checkpoint_progress tables
- NarratorScript generation via Anthropic (AI Teacher persona, German)
- TTS batch synthesis + interactive video pipeline (slides + checkpoint slides + FFmpeg)
- 4 new API endpoints: generate-interactive, interactive-manifest, checkpoint submit, checkpoint progress
- InteractiveVideoPlayer component (HTML5 Video, quiz overlay, seek protection, progress tracking)
- Learner portal integration with automatic completion on all checkpoints passed
- 30 new tests (handler validation + grading logic + manifest/progress + seek protection)

Training Blocks:
- Block generator, block store, block config CRUD + preview/generate endpoints
- Migration 021: training_blocks schema

Control Generator + Canonical Library:
- Control generator routes + service enhancements
- Canonical control library helpers, sidebar entry
- Citation backfill service + tests
- CE libraries data (hazard, protection, evidence, lifecycle, components)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

developer-portal/components/DevPortalLayout.tsx

@@ -54,6 +54,7 @@ const navigation: NavItem[] = [
       { title: 'RAG Search API', href: '/api/rag' },
       { title: 'Generation API', href: '/api/generate' },
       { title: 'Export API', href: '/api/export' },
+      { title: 'Training API', href: '/api/training' },
     ],
   },
   {