actions::destroy syncs meta after lifecycle

once nixos-container destroy lands + per-agent state cleanup is
done, rerender the meta flake from the remaining containers so
the destroyed agent's input + nixosConfiguration drop off and
its flake.lock entry vanishes. log + keep going on meta-sync
failure — the destroy already succeeded at the lifecycle level,
so meta drift here is just bookkeeping. new public
lifecycle::agents_for_meta_listing exposes the agent
enumeration for callers outside the module.

hive-c0re/src/lifecycle.rs

@@ -213,6 +213,14 @@ async fn agents_after_spawn(name: &str) -> Result<Vec<crate::meta::AgentSpec>> {
     agents_for_meta(Some(name)).await
 }
 
+/// Public enumeration of currently-existing agents (whatever
+/// `nixos-container list` says), sorted, no extras. For callers
+/// outside this module that need to reseed meta after lifecycle
+/// changes — destroy, startup reconciliation, etc.
+pub async fn agents_for_meta_listing() -> Result<Vec<crate::meta::AgentSpec>> {
+    agents_for_meta(None).await
+}
+
 pub async fn kill(name: &str) -> Result<()> {
     validate(name)?;
     let container = container_name(name);