Add network_routes to dcn1 and dcn2 stacks for ci-framework

Add network-specific routes to dcn_nostorage.yaml stack configurations
to enable ci-framework's os-net-config template to render cross-site
routes for DCN compute nodes.

Problem:
- ci-framework pre-generates /etc/os-net-config/tripleo_config.yaml
  via ansible template before TripleO Heat deployment runs
- This bypasses TripleO Heat NIC templates completely
- Routes defined in network_data.yaml.j2 are never rendered to
  compute nodes

Solution:
- Add network_routes configuration to dcn1 and dcn2 stacks in
  dcn_nostorage.yaml
- ci-framework's os_net_config_overcloud.yml.j2 template will consume
  these routes and render them to /etc/os-net-config/tripleo_config.yaml

Routes Added:
- DCN1: Routes to central (172.17/18/19.0.0/24) and dcn2
  (172.17/18/19.20.0/24) via appropriate gateways
- DCN2: Routes to central (172.17/18/19.0.0/24) and dcn1
  (172.17/18/19.10.0/24) via appropriate gateways

This enables DCN compute nodes to reach OVN southbound DB and other
services on central controllers using the correct source IP addresses.

Related: Commit bfc6d4d added routes to network_data.yaml.j2, but
those routes were never being used due to ci-framework bypassing
Heat templates.

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: John Fulton <fulton@redhat.com>

Author: 2 people

scenarios/dcn_nostorage.yaml

@@ -161,6 +161,22 @@ stacks:
       - ip_netmask: 0.0.0.0/0
         next_hop: 192.168.133.1
         default: true
+    network_routes:
+      internalapidcn1:
+        - ip_netmask: 172.17.0.0/24
+          next_hop: 172.17.10.1
+        - ip_netmask: 172.17.20.0/24
+          next_hop: 172.17.10.1
+      storagedcn1:
+        - ip_netmask: 172.18.0.0/24
+          next_hop: 172.18.10.1
+        - ip_netmask: 172.18.20.0/24
+          next_hop: 172.18.10.1
+      tenantdcn1:
+        - ip_netmask: 172.19.0.0/24
+          next_hop: 172.19.10.1
+        - ip_netmask: 172.19.20.0/24
+          next_hop: 172.19.10.1
   - stackname: dcn2
     args:
       - "--override-ansible-cfg /home/zuul/ansible_config.cfg"
@@ -190,3 +206,19 @@ stacks:
       - ip_netmask: 0.0.0.0/0
         next_hop: 192.168.144.1
         default: true
+    network_routes:
+      internalapidcn2:
+        - ip_netmask: 172.17.0.0/24
+          next_hop: 172.17.20.1
+        - ip_netmask: 172.17.10.0/24
+          next_hop: 172.17.20.1
+      storagedcn2:
+        - ip_netmask: 172.18.0.0/24
+          next_hop: 172.18.20.1
+        - ip_netmask: 172.18.10.0/24
+          next_hop: 172.18.20.1
+      tenantdcn2:
+        - ip_netmask: 172.19.0.0/24
+          next_hop: 172.19.20.1
+        - ip_netmask: 172.19.10.0/24
+          next_hop: 172.19.20.1