API route /api/contact calls sendeKontaktEmail and returns ok/error.
On total failure (no SMTP, no queue) logs full contact data to server log.
Contact.tsx is now a client component: shows spinner while sending,
success state ("Anfrage gesendet") on ok, error banner with message on failure.
queueEmail now returns boolean; sendWithFallback returns { sent, queued }.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds lib/mailer.ts (sendeKontaktEmail, MBO-Tech-IT branding),
lib/email-queue.ts (Supabase-fallback, graceful no-op when not configured),
lib/supabase.ts (stub for later integration), admin API routes for
SMTP-test and queue management, and instrumentation.ts for the queue worker.
Excludes modules/ from TypeScript compilation.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>