fix(agent-manager): hide changes panel during worktree setup (#7196)

Close diff and review panels when a worktree enters setup mode and
contain the diff header z-index so it cannot bleed through the setup
overlay.

packages/kilo-vscode/webview-ui/agent-manager/AgentManagerApp.tsx

@@ -1099,6 +1099,9 @@ const AgentManagerContent: Component = () => {
             )
             setSelection(ev.worktreeId)
           }
+          // Close diff/review panels — nothing to show during setup
+          setDiffOpen(false)
+          setReviewActive(false)
           setSetup({ active: true, message: ev.message, branch: ev.branch, worktreeId: ev.worktreeId })
         }
       }

packages/kilo-vscode/webview-ui/agent-manager/agent-manager.css

@@ -885,6 +885,7 @@ button.am-section-toggle:hover .am-section-label {
   flex-direction: column;
   flex: 1;
   min-height: 0;
+  isolation: isolate;
 }
 
 .am-detail-split {