Add CLAUDE.md, MkDocs docs, .claude/rules

- CLAUDE.md: Comprehensive documentation for Lehrer KI platform
- docs-src: Klausur, Voice, Agent-Core, KI-Pipeline docs
- mkdocs.yml: Lehrer-specific nav with blue theme
- docker-compose: Added docs service (port 8010, profile: docs)
- .claude/rules: testing, docs, open-source, abiturkorrektur, vocab-worksheet, multi-agent, experimental-dashboard

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

docker-compose.yml

@@ -453,3 +453,24 @@ services:
     restart: unless-stopped
     networks:
       - breakpilot-network
+
+  # =========================================================
+  # DOCUMENTATION
+  # =========================================================
+  docs:
+    build:
+      context: .
+      dockerfile: docs-src/Dockerfile
+    container_name: bp-lehrer-docs
+    profiles: [docs]
+    platform: linux/arm64
+    ports:
+      - "8010:80"
+    healthcheck:
+      test: ["CMD", "wget", "-q", "--spider", "http://127.0.0.1:80/"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+    restart: unless-stopped
+    networks:
+      - breakpilot-network