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>

Caddyfile

@@ -1,4 +1,8 @@
-:80 {
+{
+    auto_https off
+}
+
+http://document.hyungi.net {
     encode gzip
 
     # API + 문서 → FastAPI
@@ -25,7 +29,7 @@
 }
 
 # Synology Office 프록시
-office.hyungi.net {
+http://office.hyungi.net {
     reverse_proxy https://ds1525.hyungi.net:5001 {
         header_up Host {upstream_hostport}
         transport http {