v1.3.2: SEO fixes + map bugfixes

SEO:
- Landing page converted to Server Component (SSR)
- Extracted NavAuthButtons + ContactForm as client islands
- Removed fake aggregateRating from JSON-LD
- Added FAQPage JSON-LD schema (7 questions)
- Extended sitemap: /datenschutz, /spenden, /demo

Map fixes:
- WebGL context lost recovery (black tiles after inactivity)
- Page visibility handler for tile reload on tab switch
- Arrow direction: geographic bearing instead of screen angle
- All markers rotationAlignment viewport->map (geographic orientation)
- DEL key now deletes selected lines/polygons/arrows (not just symbols)
- Default drawing color: black

src/components/landing/contact-form.tsx

@@ -0,0 +1,105 @@
+'use client'
+
+import { useState } from 'react'
+import { Button } from '@/components/ui/button'
+import { Loader2, Send, Check } from 'lucide-react'
+
+export function ContactForm() {
+  const [name, setName] = useState('')
+  const [email, setEmail] = useState('')
+  const [message, setMessage] = useState('')
+  const [sending, setSending] = useState(false)
+  const [sent, setSent] = useState(false)
+  const [error, setError] = useState('')
+
+  const handleSubmit = async (e: React.FormEvent) => {
+    e.preventDefault()
+    setSending(true)
+    setError('')
+    try {
+      const res = await fetch('/api/contact', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ name, email, message }),
+      })
+      if (res.ok) {
+        setSent(true)
+        setName('')
+        setEmail('')
+        setMessage('')
+      } else {
+        const data = await res.json()
+        setError(data.error || 'Senden fehlgeschlagen')
+      }
+    } catch {
+      setError('Verbindung fehlgeschlagen')
+    } finally {
+      setSending(false)
+    }
+  }
+
+  if (sent) {
+    return (
+      <div className="text-center bg-green-50 border border-green-200 rounded-xl p-8">
+        <Check className="w-10 h-10 text-green-600 mx-auto mb-3" />
+        <h3 className="font-semibold text-green-900 text-lg">Nachricht gesendet!</h3>
+        <p className="text-green-700 mt-2">Vielen Dank! Ich melde mich so schnell wie möglich.</p>
+        <Button variant="outline" className="mt-4" onClick={() => setSent(false)}>
+          Weitere Nachricht senden
+        </Button>
+      </div>
+    )
+  }
+
+  return (
+    <form onSubmit={handleSubmit} className="space-y-4">
+      <div className="grid sm:grid-cols-2 gap-4">
+        <div>
+          <label className="block text-sm font-medium text-gray-700 mb-1">Name</label>
+          <input
+            type="text"
+            value={name}
+            onChange={e => setName(e.target.value)}
+            required
+            placeholder="Dein Name"
+            className="w-full rounded-lg border border-gray-300 px-4 py-2.5 text-sm focus:outline-none focus:ring-2 focus:ring-red-500 focus:border-transparent"
+          />
+        </div>
+        <div>
+          <label className="block text-sm font-medium text-gray-700 mb-1">E-Mail</label>
+          <input
+            type="email"
+            value={email}
+            onChange={e => setEmail(e.target.value)}
+            required
+            placeholder="name@feuerwehr.ch"
+            className="w-full rounded-lg border border-gray-300 px-4 py-2.5 text-sm focus:outline-none focus:ring-2 focus:ring-red-500 focus:border-transparent"
+          />
+        </div>
+      </div>
+      <div>
+        <label className="block text-sm font-medium text-gray-700 mb-1">Nachricht</label>
+        <textarea
+          value={message}
+          onChange={e => setMessage(e.target.value)}
+          required
+          rows={5}
+          placeholder="Deine Nachricht..."
+          className="w-full rounded-lg border border-gray-300 px-4 py-2.5 text-sm focus:outline-none focus:ring-2 focus:ring-red-500 focus:border-transparent resize-none"
+        />
+      </div>
+      {error && <p className="text-sm text-red-600">{error}</p>}
+      <Button
+        type="submit"
+        className="bg-red-600 hover:bg-red-700"
+        disabled={sending || !name || !email || !message}
+      >
+        {sending ? (
+          <><Loader2 className="w-4 h-4 mr-2 animate-spin" /> Wird gesendet...</>
+        ) : (
+          <><Send className="w-4 h-4 mr-2" /> Nachricht senden</>
+        )}
+      </Button>
+    </form>
+  )
+}