Add "View Networks": front-facing subnet browse + detail with attached devices

Subnets previously lived only under Settings, easily confused with the Network
Devices asset list. Add a front-facing browse + detail:

- Nav: rename "Network" -> "Network Devices"; add "View Networks" (subnets), both
  under Assets (network plugin get_navigation_items; frontend fallback matched).
- /networks (SubnetsBrowse): all subnets with name / CIDR / type / VLAN / notes,
  searchable, row-click to detail.
- /networks/:id (SubnetDetail): the subnet (CIDR, network address, type, VLAN,
  gateway, notes) plus the network devices whose primary IP falls inside its
  CIDR - get_subnet now computes that membership in Python (a device's IP lives
  in a Communication row, so it is not a plain SQL join).

Verified on the import DB: 37 networks list (real WJ subnets), detail renders.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/network/api/routes.py

@@ -814,7 +814,8 @@ def list_subnets():
 @network_bp.route('/subnets/<int:subnet_id>', methods=['GET'])
 @jwt_required(optional=True)
 def get_subnet(subnet_id: int):
-    """Get a single subnet."""
+    """Get a single subnet plus the network devices whose primary IP falls in
+    its CIDR range."""
     subnet = db.session.get(Subnet, subnet_id)
 
     if not subnet:
@@ -824,7 +825,42 @@ def get_subnet(subnet_id: int):
             http_code=404
         )
 
-    return success_response(subnet.to_dict())
+    data = subnet.to_dict()
+    data['devices'] = _devices_in_subnet(subnet.cidr)
+    return success_response(data)
+
+
+def _devices_in_subnet(cidr):
+    """Network devices (with their primary IP) whose IP is inside cidr. Matching
+    is done in Python because a device's IP lives in a Communication row, not a
+    column, so it cannot be a simple SQL join."""
+    import ipaddress
+    try:
+        net = ipaddress.ip_network(cidr, strict=False)
+    except (ValueError, TypeError):
+        return []
+    result = []
+    for netdev in NetworkDevice.query.all():
+        ip = _primary_ip(netdev.assetid)
+        if not ip:
+            continue
+        try:
+            if ipaddress.ip_address(ip.strip()) in net:
+                asset = netdev.asset
+                result.append({
+                    'networkdeviceid': netdev.networkdeviceid,
+                    'assetid': netdev.assetid,
+                    'assetnumber': asset.assetnumber if asset else None,
+                    'name': asset.name if asset else None,
+                    'hostname': netdev.hostname,
+                    'ipaddress': ip,
+                    'networkdevicetypename': (netdev.networkdevicetype.networkdevicetype
+                                              if netdev.networkdevicetype else None),
+                })
+        except (ValueError, TypeError):
+            continue
+    result.sort(key=lambda d: d['ipaddress'])
+    return result
 
 
 @network_bp.route('/subnets', methods=['POST'])

plugins/network/plugin.py

@@ -208,11 +208,17 @@ class NetworkPlugin(BasePlugin):
         """Return navigation menu items."""
         return [
             {
-                'name': 'Network',
+                'name': 'Network Devices',
                 'icon': 'network-wired',
                 'route': '/network',
                 'position': 18,
             },
+            {
+                'name': 'View Networks',
+                'icon': 'globe',
+                'route': '/networks',
+                'position': 19,
+            },
         ]
 
     def get_permissions(self) -> List: