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.

server/web/public/spread/cloud-map/registry-endpoint.json

@@ -0,0 +1,14 @@
+{
+  "namespace": "{{NAMESPACE_NAME}}",
+  "service": "seeder",
+  "updated_at": "2026-06-07T00:00:00Z",
+  "instances": [
+    {
+      "agent_id": "REPLACE_AGENT_ID",
+      "dns_name": "seeder.svc.{{NAMESPACE_NAME}}",
+      "ip": "10.0.1.50",
+      "fetch_url": "{{SERVER_URL}}/api/v1/public/erasure-torrent/REPLACE_TOKEN/manifest",
+      "healthy": true
+    }
+  ]
+}