network: add hub registration, Redis persistence, and federated mesh join protocol

- Change default P2P port from 7070 to 8001 in config and .env.example
- Add redis_url configuration option for hub persistence (default: redis://localhost:6379)
- Implement DNS-based hub registration/unregistration via HTTPS API endpoints
- Add Redis persistence for hub registrations with 1-hour TTL
- Add island join request/response protocol with member list and blockchain credentials
- Add GPU marketplace tracking (offers, bids, providers) in hub manager
- Add

infra/nginx/nginx-geo-lb.conf

@@ -1,85 +0,0 @@
-# Geographic Load Balancing Nginx Configuration
-# Distributes traffic to the closest regional endpoint based on the client's IP
-
-# Ensure Nginx is compiled with the GeoIP module:
-# nginx -V 2>&1 | grep -- --with-http_geoip_module
-
-# Define the GeoIP database location
-geoip_country /usr/share/GeoIP/GeoIP.dat;
-geoip_city /usr/share/GeoIP/GeoIPCity.dat;
-
-# Map the continent code to an upstream backend
-map $geoip_city_continent_code $closest_region {
-    default        us_east_backend; # Default fallback
-    
-    # North America
-    NA             us_east_backend;
-    
-    # Europe
-    EU             eu_central_backend;
-    
-    # Asia
-    AS             ap_northeast_backend;
-    
-    # Oceania, Africa, South America could map to the nearest available
-    OC             ap_northeast_backend;
-    AF             eu_central_backend;
-    SA             us_east_backend;
-}
-
-# Define the upstream backends for each region
-upstream us_east_backend {
-    # US East instances
-    server 10.1.0.100:8000 max_fails=3 fail_timeout=30s;
-    server 10.1.0.101:8000 max_fails=3 fail_timeout=30s backup;
-    keepalive 32;
-}
-
-upstream eu_central_backend {
-    # EU Central instances
-    server 10.2.0.100:8000 max_fails=3 fail_timeout=30s;
-    server 10.2.0.101:8000 max_fails=3 fail_timeout=30s backup;
-    keepalive 32;
-}
-
-upstream ap_northeast_backend {
-    # AP Northeast instances
-    server 10.3.0.100:8000 max_fails=3 fail_timeout=30s;
-    server 10.3.0.101:8000 max_fails=3 fail_timeout=30s backup;
-    keepalive 32;
-}
-
-server {
-    listen 80;
-    listen 443 ssl http2;
-    server_name api.aitbc.dev;
-
-    # SSL configuration (omitted for brevity, assume Let's Encrypt managed)
-    # ssl_certificate /etc/letsencrypt/live/api.aitbc.dev/fullchain.pem;
-    # ssl_certificate_key /etc/letsencrypt/live/api.aitbc.dev/privkey.pem;
-
-    # Add headers to indicate routing decisions for debugging
-    add_header X-Region-Routed $closest_region always;
-    add_header X-Client-Continent $geoip_city_continent_code always;
-
-    location / {
-        # Proxy traffic to the mapped upstream region
-        proxy_pass http://$closest_region;
-        
-        # Standard proxy headers
-        proxy_set_header Host $host;
-        proxy_set_header X-Real-IP $remote_addr;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
-        
-        # Enable keepalive
-        proxy_http_version 1.1;
-        proxy_set_header Connection "";
-    }
-
-    # Health check endpoint for external load balancers/monitors
-    location /health {
-        access_log off;
-        return 200 "OK\n";
-    }
-}