feat: 新增 core/agents 模块和 nanobot

- 新增 agents 模块，包含 agent、api、skills 等子模块
- 新增 nanobot 项目，支持多渠道集成
- 添加启动脚本 start-all.bat 和 start-all.sh

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

core/nanobot/docker-compose.yml

@@ -0,0 +1,31 @@
+x-common-config: &common-config
+  build:
+    context: .
+    dockerfile: Dockerfile
+  volumes:
+    - ~/.nanobot:/root/.nanobot
+
+services:
+  nanobot-gateway:
+    container_name: nanobot-gateway
+    <<: *common-config
+    command: ["gateway"]
+    restart: unless-stopped
+    ports:
+      - 18790:18790
+    deploy:
+      resources:
+        limits:
+          cpus: '1'
+          memory: 1G
+        reservations:
+          cpus: '0.25'
+          memory: 256M
+  
+  nanobot-cli:
+    <<: *common-config
+    profiles:
+      - cli
+    command: ["status"]
+    stdin_open: true
+    tty: true