style(ui): enhance agent model layout with margin adjustments and flexbox for actions

ui/src/styles/components.css

@@ -2032,6 +2032,15 @@
 .agent-model-select {
   display: grid;
   gap: 12px;
+  margin-top: 12px;
+}
+
+.agent-model-actions {
+  display: flex;
+  gap: 8px;
+  align-items: flex-end;
+  flex-shrink: 0;
+  padding-bottom: 2px;
 }
 
 .agent-model-meta {
@@ -2269,9 +2278,9 @@
 
 .agent-identity-card {
   display: flex;
-  gap: 16px;
+  gap: 12px;
   align-items: center;
-  padding: 16px;
+  padding: 12px;
   border: 1px solid var(--border);
   border-radius: var(--radius-lg);
   background: var(--bg-elevated);

ui/src/ui/views/agents.ts

@@ -220,9 +220,6 @@ export function renderAgents(props: AgentsProps) {
                         defaultId,
                         configForm: props.config.form,
                         agentFilesList: props.agentFiles.list,
-                        agentIdentity: props.agentIdentityById[selectedAgent.id] ?? null,
-                        agentIdentityError: props.agentIdentityError,
-                        agentIdentityLoading: props.agentIdentityLoading,
                         configLoading: props.config.loading,
                         configSaving: props.config.saving,
                         configDirty: props.config.dirty,