infra: migrate application from Mac mini to GPU server

- Integrate ollama + ai-gateway into root docker-compose.yml
  (NVIDIA GPU runtime, single compose for all services)
- Change NAS mount from SMB (NAS_SMB_PATH) to NFS (NAS_NFS_PATH)
  Default: /mnt/nas/Document_Server (fstab registered on GPU server)
- Update config.yaml AI endpoints:
  primary → Mac mini MLX via Tailscale (100.76.254.116:8800)
  fallback/embedding/vision/rerank → ollama (same Docker network)
  gateway → ai-gateway (same Docker network)
- Update credentials.env.example (remove GPU_SERVER_IP, add NFS path)
- Mark gpu-server/docker-compose.yml as deprecated
- Update CLAUDE.md network diagram and AI model config
- Update architecture.md, deploy.md, devlog.md for GPU server as main
- Caddyfile: auto_https off, HTTP only (TLS at upstream proxy)
- Caddy port: 127.0.0.1:8080:80 (localhost only)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

gpu-server/docker-compose.yml

@@ -1,4 +1,7 @@
-version: '3.8'
+# ═══════════════════════════════════════════════════
+# 이 파일은 더 이상 사용하지 않음.
+# 루트 docker-compose.yml로 통합됨 (2026-04-03).
+# ═══════════════════════════════════════════════════
 
 services:
   ollama: