fix: persist future network host approvals across sessions (#14619)

## Summary
- apply persisted execpolicy network rules when booting the managed
network proxy
- pass the current execpolicy into managed proxy startup so host
approvals selected with "allow this host in the future" survive new
sessions

codex-rs/core/src/codex.rs

@@ -1163,12 +1163,22 @@ impl Session {
 
     async fn start_managed_network_proxy(
         spec: &crate::config::NetworkProxySpec,
+        exec_policy: &codex_execpolicy::Policy,
         sandbox_policy: &SandboxPolicy,
         network_policy_decider: Option<Arc<dyn codex_network_proxy::NetworkPolicyDecider>>,
         blocked_request_observer: Option<Arc<dyn codex_network_proxy::BlockedRequestObserver>>,
         managed_network_requirements_enabled: bool,
         audit_metadata: NetworkProxyAuditMetadata,
     ) -> anyhow::Result<(StartedNetworkProxy, SessionNetworkProxyRuntime)> {
+        let spec = spec
+            .with_exec_policy_network_rules(exec_policy)
+            .map_err(|err| {
+                tracing::warn!(
+                    "failed to apply execpolicy network rules to managed proxy; continuing with configured network policy: {err}"
+                );
+                err
+            })
+            .unwrap_or_else(|_| spec.clone());
         let network_proxy = spec
             .start_proxy(
                 sandbox_policy,
@@ -1692,8 +1702,10 @@ impl Session {
                 });
         let (network_proxy, session_network_proxy) =
             if let Some(spec) = config.permissions.network.as_ref() {
+                let current_exec_policy = exec_policy.current();
                 let (network_proxy, session_network_proxy) = Self::start_managed_network_proxy(
                     spec,
+                    current_exec_policy.as_ref(),
                     config.permissions.sandbox_policy.get(),
                     network_policy_decider.as_ref().map(Arc::clone),
                     blocked_request_observer.as_ref().map(Arc::clone),