fix(#1096): remove container name/port chip from dashboard card

Drop the 'h-sock :8421' meta span from the agent card head.
ContainerView.container is now #[serde(skip)] since no frontend
code reads it; the field stays in Rust for internal use.
c.port remains serialized — used for fallback agent UI URLs.

hive-c0re/src/container_view.rs

@@ -30,7 +30,9 @@ pub struct DashboardLink {
 pub struct ContainerView {
     /// Logical agent name (no `h-` prefix). Used in action URLs.
     pub name: String,
-    /// Container name as nixos-container sees it (`h-foo`).
+    /// Container name as nixos-container sees it (`h-foo`). Internal only;
+    /// not serialized to API responses since the dashboard no longer displays it.
+    #[serde(skip)]
     pub container: String,
     /// True when this is the manager agent. Informational — not used
     /// to gate any server-side actions. Computed from `name ==