feat: integrate docs chat widget in EPD layout (E4)

- Add DocsChatWidget to epd-layout-client.tsx
- Widget now visible for all authenticated EPD users
- Update bouwplan status: all epics complete

Completes AI Documentatie Assistent feature (E0-E4, 12 stories)

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

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

app/epd/components/epd-layout-client.tsx

@@ -3,6 +3,7 @@
 import type { ReactNode } from 'react';
 import { EPDHeader } from './epd-header';
 import { PatientProvider } from './patient-context';
+import { DocsChatWidget } from '@/components/docs-chat';
 
 interface EPDLayoutClientProps {
   children: ReactNode;
@@ -19,6 +20,9 @@ export function EPDLayoutClient({ children }: EPDLayoutClientProps) {
         <main className="flex-1 overflow-auto bg-white">
           {children}
         </main>
+
+        {/* AI Documentation Assistant */}
+        <DocsChatWidget />
       </div>
     </PatientProvider>
   );

docs/specs/ai-integratie/bouwplan-ai-docs-assistent-v1.md

@@ -66,7 +66,7 @@
 | E1 | Knowledge Services | CategoryDetector, KnowledgeLoader, PromptBuilder | ✅ Done | 3 |
 | E2 | API Endpoint | Streaming Claude integratie | ✅ Done | 1 |
 | E3 | Chat UI Components | Widget, messages, input | ✅ Done | 4 |
-| E4 | Integratie & Testing | Widget in EPD, testen | ⏳ To Do | 2 |
+| E4 | Integratie & Testing | Widget in EPD, testen | ✅ Done | 2 |
 
 **Totaal:** 12 stories, ~18 story points
 
@@ -213,8 +213,8 @@ components/docs-chat/
 
 | Story ID | Beschrijving | Acceptatiecriteria | Status | SP |
 |----------|--------------|---------------------|--------|-----|
-| E4.S1 | Widget integratie | `DocsChatWidget` in EPD layout, alleen ingelogde users | ⏳ | 1 |
-| E4.S2 | Smoke tests | Happy flow, error states, category detection werkt | ⏳ | 1 |
+| E4.S1 | Widget integratie | `DocsChatWidget` in EPD layout, alleen ingelogde users | ✅ | 1 |
+| E4.S2 | Smoke tests | Happy flow, error states, category detection werkt | ✅ | 1 |
 
 **Te wijzigen bestand:**
 ```