feat(swift): voeg chat messages en styling toe (E2.S1-S2)

E2.S1 - Store uitbreiding (2 SP)
- ChatMessage, ChatAction, ChatMessageType types toegevoegd
- chatMessages[], isStreaming, pendingAction state
- addChatMessage, updateLastMessage, clearChat, setStreaming actions

E2.S2 - ChatMessage component (3 SP)
- Herbruikbare ChatMessage component met 4 message types
- MESSAGE_STYLES config (user/assistant/system/error)
- User: amber bubble rechts, rounded-tr-sm
- Assistant: slate bubble links, rounded-tl-sm
- System: centered, transparent, italic
- Error: red bubble links
- Optional timestamp support (NL locale)
- Demo messages in ChatPanel voor testing

Components Created:
- components/swift/chat/chat-message.tsx (77 regels)
- components/swift/chat/chat-panel.tsx (102 regels)

Store Updated:
- stores/swift-store.ts (+87 regels) - Chat state en actions

Epic 2 Progress: 2/5 stories compleet (5 SP / 13 SP = 38%)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

components/swift/chat/chat-panel.tsx

@@ -0,0 +1,102 @@
+'use client';
+
+/**
+ * Chat Panel (v3.0)
+ *
+ * Chat interface met message list en input.
+ * Toont chat messages met verschillende types (user, assistant, system, error).
+ *
+ * Epic: E2 (Chat Panel & Messages)
+ * Story: E2.S2 (ChatMessage component) - testing
+ */
+
+import { ChatMessage } from './chat-message';
+import { useSwiftStore } from '@/stores/swift-store';
+
+export function ChatPanel() {
+  const chatMessages = useSwiftStore((s) => s.chatMessages);
+
+  // Demo messages for testing E2.S2 (will be removed in E2.S3)
+  const demoMessages = chatMessages.length === 0 ? [
+    {
+      id: '1',
+      type: 'system' as const,
+      content: 'Welkom bij Swift Medical Scribe v3.0',
+      timestamp: new Date(),
+    },
+    {
+      id: '2',
+      type: 'user' as const,
+      content: 'Notitie voor Jan: medicatie gegeven om 14:00',
+      timestamp: new Date(),
+    },
+    {
+      id: '3',
+      type: 'assistant' as const,
+      content: 'Ik begrijp dat je een notitie wilt maken voor Jan over medicatie. Ik open een dagnotitie voor je waarin je dit kunt vastleggen.',
+      timestamp: new Date(),
+    },
+    {
+      id: '4',
+      type: 'error' as const,
+      content: 'Er ging iets mis met de verbinding. Probeer het opnieuw.',
+      timestamp: new Date(),
+    },
+  ] : chatMessages;
+
+  const hasMessages = demoMessages.length > 0;
+
+  return (
+    <div className="h-full flex flex-col bg-white">
+      {/* Chat messages area */}
+      <div className="flex-1 overflow-auto p-6">
+        {hasMessages ? (
+          <div className="flex flex-col space-y-3">
+            {demoMessages.map((message) => (
+              <ChatMessage key={message.id} message={message} showTimestamp />
+            ))}
+          </div>
+        ) : (
+          <div className="flex items-center justify-center h-full">
+            <div className="max-w-md text-center text-slate-500">
+              <div className="text-4xl mb-4">💬</div>
+              <h3 className="text-lg font-medium text-slate-700 mb-2">
+                Welkom bij Swift Medical Scribe
+              </h3>
+              <p className="text-sm mb-4">
+                Typ of spreek wat je wilt doen...
+              </p>
+              <div className="text-left text-sm space-y-1 bg-slate-50 rounded-lg p-4">
+                <p className="font-medium text-slate-700 mb-2">Voorbeelden:</p>
+                <p>• &ldquo;Notitie voor Jan: medicatie gegeven&rdquo;</p>
+                <p>• &ldquo;Zoek Marie van den Berg&rdquo;</p>
+                <p>• &ldquo;Maak overdracht voor deze dienst&rdquo;</p>
+              </div>
+            </div>
+          </div>
+        )}
+      </div>
+
+      {/* Chat input - placeholder */}
+      <div className="border-t border-slate-200 p-4">
+        <div className="relative">
+          <input
+            type="text"
+            placeholder="Typ of spreek wat je wilt doen..."
+            className="w-full px-4 py-3 pr-12 rounded-lg border border-slate-300 focus:border-brand-600 focus:ring-2 focus:ring-brand-600/20 outline-none text-slate-900 placeholder:text-slate-400"
+            disabled
+          />
+          <button
+            className="absolute right-3 top-1/2 -translate-y-1/2 text-slate-400"
+            disabled
+          >
+            🎤
+          </button>
+        </div>
+        <p className="text-xs text-slate-400 mt-2">
+          E2.S2 compleet: ChatMessage component werkend ✓
+        </p>
+      </div>
+    </div>
+  );
+}