fix(admin-v2): Restore complete admin-v2 application

The admin-v2 application was incomplete in the repository. This commit
restores all missing components:

- Admin pages (76 pages): dashboard, ai, compliance, dsgvo, education,
  infrastructure, communication, development, onboarding, rbac
- SDK pages (45 pages): tom, dsfa, vvt, loeschfristen, einwilligungen,
  vendor-compliance, tom-generator, dsr, and more
- Developer portal (25 pages): API docs, SDK guides, frameworks
- All components, lib files, hooks, and types
- Updated package.json with all dependencies

The issue was caused by incomplete initial repository state - the full
admin-v2 codebase existed in backend/admin-v2 and docs-src/admin-v2
but was never fully synced to the main admin-v2 directory.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

admin-v2/app/api/admin/mail/route.ts

@@ -0,0 +1,81 @@
+import { NextResponse } from 'next/server'
+
+/**
+ * Server-side proxy for Mailpit API
+ * Avoids CORS and mixed-content issues by fetching from server
+ */
+
+// Use internal Docker hostname when running in container
+const getMailpitHost = (): string => {
+  return process.env.BACKEND_URL ? 'mailpit' : 'localhost'
+}
+
+export async function GET() {
+  const host = getMailpitHost()
+  const mailpitUrl = `http://${host}:8025/api/v1/info`
+
+  try {
+    const response = await fetch(mailpitUrl, {
+      method: 'GET',
+      signal: AbortSignal.timeout(5000),
+    })
+
+    if (!response.ok) {
+      return NextResponse.json(
+        { error: 'Mailpit API error', status: response.status },
+        { status: response.status }
+      )
+    }
+
+    const data = await response.json()
+
+    // Transform Mailpit response to our expected format
+    return NextResponse.json({
+      stats: {
+        totalAccounts: 1,
+        activeAccounts: 1,
+        totalEmails: data.Messages || 0,
+        unreadEmails: data.Unread || 0,
+        totalTasks: 0,
+        pendingTasks: 0,
+        overdueTasks: 0,
+        aiAnalyzedCount: 0,
+        lastSyncTime: new Date().toISOString(),
+      },
+      accounts: [{
+        id: 'mailpit-dev',
+        email: 'dev@mailpit.local',
+        displayName: 'Mailpit (Development)',
+        imapHost: 'mailpit',
+        imapPort: 1143,
+        smtpHost: 'mailpit',
+        smtpPort: 1025,
+        status: 'active' as const,
+        lastSync: new Date().toISOString(),
+        emailCount: data.Messages || 0,
+        unreadCount: data.Unread || 0,
+        createdAt: new Date().toISOString(),
+      }],
+      syncStatus: {
+        running: false,
+        accountsInProgress: [],
+        lastCompleted: new Date().toISOString(),
+        errors: [],
+      },
+      mailpitInfo: {
+        version: data.Version,
+        databaseSize: data.DatabaseSize,
+        uptime: data.RuntimeStats?.Uptime,
+      }
+    })
+  } catch (error) {
+    console.error('Failed to fetch from Mailpit:', error)
+    return NextResponse.json(
+      {
+        error: 'Failed to connect to Mailpit',
+        details: error instanceof Error ? error.message : 'Unknown error'
+      },
+      { status: 503 }
+    )
+  }
+}