Add Cloud Map seeder discovery with VPC Lattice operator templates.

Agents poll AETHERFORGE_CLOUD_MAP_ENDPOINT to sync know_node gossip; deploy plans attach route_via DNS hints for standalone operator registries.

templates/cloud/cloud-map/lattice-snippet.yaml

@@ -0,0 +1,46 @@
+# VPC Lattice service network snippet (operator-owned AWS account).
+# Replace placeholders before apply. Standalone mode only needs the HTTP registry URL.
+#
+# After apply, expose registry-endpoint.json via Lattice HTTPS listener or CloudFront.
+
+AWSTemplateFormatVersion: "2010-09-09"
+Description: AetherForge seeder discovery via VPC Lattice + Cloud Map namespace
+
+Parameters:
+  NamespaceName:
+    Type: String
+    Default: "{{NAMESPACE_NAME}}"
+  ServiceName:
+    Type: String
+    Default: seeder
+  RegistryURL:
+    Type: String
+    Description: HTTPS URL agents poll (maps to AETHERFORGE_CLOUD_MAP_ENDPOINT)
+    Default: "{{SERVER_URL}}/api/v1/public/cloud-map/registry-endpoint.json"
+
+Resources:
+  SeederServiceNetwork:
+    Type: AWS::VpcLattice::ServiceNetwork
+    Properties:
+      Name: aetherforge-seeder-network
+      AuthType: NONE
+
+  SeederLatticeService:
+    Type: AWS::VpcLattice::Service
+    Properties:
+      Name: !Sub "${ServiceName}-lattice"
+      AuthType: NONE
+
+  SeederServiceNetworkAssociation:
+    Type: AWS::VpcLattice::ServiceNetworkServiceAssociation
+    Properties:
+      ServiceNetworkIdentifier: !GetAtt SeederServiceNetwork.Id
+      ServiceIdentifier: !GetAtt SeederLatticeService.Id
+
+Outputs:
+  CloudMapSeederDNS:
+    Description: BGP route_via hint for spread plans
+    Value: !Sub "${ServiceName}.svc.${NamespaceName}"
+  AgentRegistryEndpoint:
+    Description: Set AETHERFORGE_CLOUD_MAP_ENDPOINT to this URL
+    Value: !Ref RegistryURL