refactor: Move network configurations to machine directories

- Move network-congenital-optimist.nix to machines/congenital-optimist/
- Move network-sleeper-service.nix to machines/sleeper-service/
- Update import paths in machine configurations
- Clean up modules/network/common.nix to remove SSH duplication
- Consolidate SSH configuration in modules/security/ssh-keys.nix
- Remove machine-specific networking from shared common module

This improves dependency tracking by co-locating machine-specific
network configurations with their respective machines.

modules/network/common.nix

@@ -1,5 +1,5 @@
 # Common Network Configuration
-# Shared networking settings across all machines
+# Minimal shared networking settings across all machines
 { config, pkgs, ... }:
 
 {
@@ -8,11 +8,10 @@
     # Enable nftables by default for all machines
     nftables.enable = true;
     
-    # Common firewall settings
+    # Basic firewall settings (SSH handled by security/ssh-keys.nix)
     firewall = {
       enable = true;
-      # SSH is allowed by default on all machines
-      allowedTCPPorts = [ 22 ];
+      # SSH port is configured in modules/security/ssh-keys.nix
     };
   };
 
@@ -21,13 +20,6 @@
     # Tailscale VPN for secure remote access
     tailscale.enable = true;
     
-    # SSH access with secure defaults
-    openssh = {
-      enable = true;
-      settings = {
-        PermitRootLogin = "no";
-        PasswordAuthentication = false;
-      };
-    };
+    # Note: SSH configuration is handled by modules/security/ssh-keys.nix
   };
 }

modules/network/network-congenital-optimist.nix

@@ -1,21 +0,0 @@
-# Networking Configuration - congenital-optimist
-# AMD Threadripper workstation network setup
-{ config, pkgs, ... }:
-
-{
-  imports = [
-    ./common.nix
-  ];
-
-  # Machine-specific network configuration
-  networking = {
-    hostName = "congenital-optimist";
-    hostId = "8425e349";
-    networkmanager.enable = true;
-    
-    # Additional firewall ports for workstation services
-    firewall.allowedTCPPorts = [ 
-    ];
-  };
-
-}

modules/network/network-sleeper-service.nix

@@ -1,61 +0,0 @@
-# Networking Configuration - sleeper-service
-# Xeon file server network setup with systemd-networkd and static IPs
-{ config, pkgs, ... }:
-
-{
-  imports = [
-    ./common.nix
-  ];
-
-  # Machine-specific network configuration
-  networking = {
-    hostName = "sleeper-service";
-    hostId = "8425e349"; # Unique identifier for the machine - DO NOT CHANGE!!
-    
-    # # Enable systemd-networkd for static networking
-    # useNetworkd = false;
-    # useDHCP = true;  
-    
-    # Disable NetworkManager in favor of systemd-networkd
-    networkmanager.enable = true;
-    
-    # DNS configuration - use Pi-hole server
-    nameservers = [ "10.0.0.14" "8.8.8.8" ];  # Pi-hole server, Google DNS fallback
-    
-    # Configure static IP for the main ethernet interface
-    # interfaces.enp0s25 = {
-    #   useDHCP = false;
-    #   ipv4.addresses = [
-    #     {
-    #       address = "10.0.0.8";  # Static IP for sleeper-service (existing files.home machine)
-    #       prefixLength = 24;
-    #     }
-    #   ];
-    # };
-    
-    # Network gateway and DNS (based on nmap discovery)
-    # defaultGateway = {
-    #   address = "10.0.0.138";  # Discovered router at lan.home
-    #   interface = "enp0s25";   # Main ethernet interface
-    # };
-    # nameservers = [ "10.0.0.14" "10.0.0.138" "8.8.8.8" ];  # Pi-hole, router, Google DNS fallback
-    
-    # Additional firewall ports for file server services
-    firewall.allowedTCPPorts = [ 
-      22    # SSH
-      111   # NFS portmapper
-      2049  # NFS
-      445   # SMB/CIFS
-      139   # NetBIOS Session Service
-      # Add additional ports here as needed
-    ];
-    
-    firewall.allowedUDPPorts = [
-      22    # SSH 
-      111   # NFS portmapper
-      2049  # NFS
-      137   # NetBIOS Name Service
-      138   # NetBIOS Datagram Service
-    ];
-  };
-}

modules/security/ssh-keys.nix

@@ -3,6 +3,9 @@
 { config, pkgs, lib, ... }:
 
 {
+  # Firewall configuration for SSH
+  networking.firewall.allowedTCPPorts = [ 22 ];
+
   # Global SSH daemon configuration
   services.openssh = {
     enable = true;