fix: Restore all files lost during destructive rebase

A previous `git pull --rebase origin main` dropped 177 local commits,
losing 3400+ files across admin-v2, backend, studio-v2, website,
klausur-service, and many other services. The partial restore attempt
(660295e2) only recovered some files.

This commit restores all missing files from pre-rebase ref 98933f5e
while preserving post-rebase additions (night-scheduler, night-mode UI,
NightModeWidget dashboard integration).

Restored features include:
- AI Module Sidebar (FAB), OCR Labeling, OCR Compare
- GPU Dashboard, RAG Pipeline, Magic Help
- Klausur-Korrektur (8 files), Abitur-Archiv (5+ files)
- Companion, Zeugnisse-Crawler, Screen Flow
- Full backend, studio-v2, website, klausur-service
- All compliance SDKs, agent-core, voice-service
- CI/CD configs, documentation, scripts

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

admin-v2/app/api/sdk/v1/checkpoints/route.ts

@@ -9,18 +9,10 @@ import { NextRequest, NextResponse } from 'next/server'
 
 // Checkpoint definitions
 const CHECKPOINTS = {
-  'CP-PROF': {
-    id: 'CP-PROF',
-    step: 'company-profile',
-    name: 'Unternehmensprofil Checkpoint',
-    type: 'REQUIRED',
-    blocksProgress: true,
-    requiresReview: 'NONE',
-  },
   'CP-UC': {
     id: 'CP-UC',
-    step: 'use-case-assessment',
-    name: 'Anwendungsfall Checkpoint',
+    step: 'use-case-workshop',
+    name: 'Use Case Checkpoint',
     type: 'REQUIRED',
     blocksProgress: true,
     requiresReview: 'NONE',