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/components/layout/Sidebar.tsx

@@ -237,23 +237,44 @@ export function Sidebar({ onRoleChange }: SidebarProps) {
               {/* Category Modules */}
               {!collapsed && expandedCategories.has(category.id) && (
                 <div className="ml-4 mt-1 space-y-1">
-                  {category.modules.map((module) => (
-                    <Link
-                      key={module.id}
-                      href={module.href}
-                      className={`flex items-center gap-2 px-3 py-2 rounded-lg text-sm transition-colors ${
-                        isModuleActive(module.href)
-                          ? 'bg-primary-600 text-white'
-                          : 'text-slate-400 hover:bg-slate-800 hover:text-white'
-                      }`}
-                    >
-                      <span
-                        className="w-1.5 h-1.5 rounded-full"
-                        style={{ backgroundColor: category.color }}
-                      />
-                      <span className="truncate">{module.name}</span>
-                    </Link>
-                  ))}
+                  {(() => {
+                    // Group modules by subgroup
+                    const subgroups = new Map<string | undefined, typeof category.modules>()
+                    category.modules.forEach((module) => {
+                      const key = module.subgroup
+                      if (!subgroups.has(key)) {
+                        subgroups.set(key, [])
+                      }
+                      subgroups.get(key)!.push(module)
+                    })
+
+                    return Array.from(subgroups.entries()).map(([subgroupName, modules]) => (
+                      <div key={subgroupName || 'default'}>
+                        {subgroupName && (
+                          <div className="px-3 py-1.5 text-xs font-medium text-slate-500 uppercase tracking-wider mt-2 first:mt-0">
+                            {subgroupName}
+                          </div>
+                        )}
+                        {modules.map((module) => (
+                          <Link
+                            key={module.id}
+                            href={module.href}
+                            className={`flex items-center gap-2 px-3 py-2 rounded-lg text-sm transition-colors ${
+                              isModuleActive(module.href)
+                                ? 'bg-primary-600 text-white'
+                                : 'text-slate-400 hover:bg-slate-800 hover:text-white'
+                            }`}
+                          >
+                            <span
+                              className="w-1.5 h-1.5 rounded-full"
+                              style={{ backgroundColor: category.color }}
+                            />
+                            <span className="truncate">{module.name}</span>
+                          </Link>
+                        ))}
+                      </div>
+                    ))
+                  })()}
                 </div>
               )}
             </div>
@@ -266,18 +287,18 @@ export function Sidebar({ onRoleChange }: SidebarProps) {
       <div className="p-4 border-t border-slate-700">
         <RoleIndicator collapsed={collapsed} onRoleChange={onRoleChange} />
 
-        <Link
-          href="/"
+        <a
+          href="https://macmini:3000/admin"
           className={`flex items-center gap-3 px-3 py-2 rounded-lg text-slate-400 hover:text-white hover:bg-slate-800 transition-colors mt-2 ${
             collapsed ? 'justify-center' : ''
           }`}
-          title="Zur Website"
+          title="Altes Admin (Port 3000)"
         >
           <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
             <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10 19l-7-7m0 0l7-7m-7 7h18" />
           </svg>
           {!collapsed && <span>Altes Admin</span>}
-        </Link>
+        </a>
       </div>
     </aside>
   )