feat(pitch-deck): Waiting-Indicator im Investor Agent Chat

Drei animierte Punkte (iMessage-Style) erscheinen sofort nach dem
Absenden und verschwinden wenn der erste Token eintrifft.

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

pitch-deck/components/ui/ChatInterface.tsx

@@ -15,6 +15,7 @@ export default function ChatInterface({ lang }: ChatInterfaceProps) {
   const [messages, setMessages] = useState<ChatMessage[]>([])
   const [input, setInput] = useState('')
   const [isStreaming, setIsStreaming] = useState(false)
+  const [isWaiting, setIsWaiting] = useState(false)
   const messagesEndRef = useRef<HTMLDivElement>(null)
   const inputRef = useRef<HTMLInputElement>(null)
 
@@ -29,6 +30,7 @@ export default function ChatInterface({ lang }: ChatInterfaceProps) {
     setInput('')
     setMessages(prev => [...prev, { role: 'user', content: message }])
     setIsStreaming(true)
+    setIsWaiting(true)
 
     try {
       const res = await fetch('/api/chat', {
@@ -47,21 +49,28 @@ export default function ChatInterface({ lang }: ChatInterfaceProps) {
       const decoder = new TextDecoder()
       let content = ''
 
-      setMessages(prev => [...prev, { role: 'assistant', content: '' }])
-
       while (true) {
         const { done, value } = await reader.read()
         if (done) break
 
-        content += decoder.decode(value, { stream: true })
-        setMessages(prev => {
-          const updated = [...prev]
-          updated[updated.length - 1] = { role: 'assistant', content }
-          return updated
-        })
+        const chunk = decoder.decode(value, { stream: true })
+        content += chunk
+
+        if (isWaiting || content.length === chunk.length) {
+          // First chunk arrived — replace waiting indicator with real content
+          setIsWaiting(false)
+          setMessages(prev => [...prev, { role: 'assistant', content }])
+        } else {
+          setMessages(prev => {
+            const updated = [...prev]
+            updated[updated.length - 1] = { role: 'assistant', content }
+            return updated
+          })
+        }
       }
     } catch (err) {
       console.error('Chat error:', err)
+      setIsWaiting(false)
       setMessages(prev => [
         ...prev,
         { role: 'assistant', content: lang === 'de'
@@ -71,6 +80,7 @@ export default function ChatInterface({ lang }: ChatInterfaceProps) {
       ])
     } finally {
       setIsStreaming(false)
+      setIsWaiting(false)
     }
   }
 
@@ -135,6 +145,33 @@ export default function ChatInterface({ lang }: ChatInterfaceProps) {
             </motion.div>
           ))}
         </AnimatePresence>
+
+        {/* Waiting indicator — shown between send and first token */}
+        <AnimatePresence>
+          {isWaiting && (
+            <motion.div
+              initial={{ opacity: 0, y: 8 }}
+              animate={{ opacity: 1, y: 0 }}
+              exit={{ opacity: 0, y: -4 }}
+              className="flex gap-3"
+            >
+              <div className="w-8 h-8 rounded-full bg-indigo-500/20 flex items-center justify-center shrink-0">
+                <Bot className="w-4 h-4 text-indigo-400" />
+              </div>
+              <div className="bg-white/[0.06] rounded-2xl px-4 py-3 flex items-center gap-1">
+                {[0, 1, 2].map(i => (
+                  <motion.span
+                    key={i}
+                    className="block w-2 h-2 rounded-full bg-indigo-400/70"
+                    animate={{ opacity: [0.3, 1, 0.3], y: [0, -4, 0] }}
+                    transition={{ duration: 0.8, repeat: Infinity, delay: i * 0.18 }}
+                  />
+                ))}
+              </div>
+            </motion.div>
+          )}
+        </AnimatePresence>
+
         <div ref={messagesEndRef} />
       </div>