Remove complex SIGHUP reload feature, use simple restart instead

- Remove tokio signal handling and mutex-based TLS acceptor reloading
- Simplify main loop back to basic connection acceptance
- Update systemd service to remove ExecReload
- Change certbot hook to use systemctl restart instead of reload
- Maintain <1s restart time for certificate updates
- Eliminate user confusion about partial config reloading

dist/INSTALL.md

@@ -202,7 +202,7 @@ See `config.toml` for all available options. Key settings:
 
 ## Certificate Management
 
-The server supports automatic certificate reloading via SIGHUP signals.
+The server uses standard systemd restart for certificate updates. Restart time is less than 1 second.
 
 ### Let's Encrypt Integration
 
@@ -210,28 +210,28 @@ For automatic certificate renewal with certbot:
 
 ```bash
 # Create post-renewal hook
-sudo tee /etc/letsencrypt/renewal-hooks/post/reload-pollux.sh > /dev/null << 'EOF'
+sudo tee /etc/letsencrypt/renewal-hooks/post/restart-pollux.sh > /dev/null << 'EOF'
 #!/bin/bash
-# Reload Pollux after Let's Encrypt certificate renewal
+# Restart Pollux after Let's Encrypt certificate renewal
 
-systemctl reload pollux
-logger -t certbot-pollux-reload "Reloaded pollux after certificate renewal"
+systemctl restart pollux
+logger -t certbot-pollux-restart "Restarted pollux after certificate renewal"
 EOF
 
 # Make it executable
-sudo chmod +x /etc/letsencrypt/renewal-hooks/post/reload-pollux.sh
+sudo chmod +x /etc/letsencrypt/renewal-hooks/post/restart-pollux.sh
 
 # Test the hook
-sudo /etc/letsencrypt/renewal-hooks/post/reload-pollux.sh
+sudo /etc/letsencrypt/renewal-hooks/post/restart-pollux.sh
 ```
 
-### Manual Certificate Reload
+### Manual Certificate Update
 
 ```bash
-# Reload certificates without restarting
-sudo systemctl reload pollux
+# Restart server to load new certificates
+sudo systemctl restart pollux
 
-# Check reload in logs
+# Check restart in logs
 sudo journalctl -u pollux -f
 ```