feat(automation): complete unified automation system redesign

Phase 4 completion:
- Add ApprovalQueue component for managing pending approvals
- Add ExecutionResult component for displaying hand/workflow results
- Update Sidebar navigation to use unified AutomationPanel
- Replace separate 'hands' and 'workflow' tabs with single 'automation' tab
- Fix TypeScript type safety issues with unknown types in JSX expressions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/src-tauri/Cargo.toml

@@ -35,3 +35,6 @@ base64 = "0.22"
 thiserror = "2"
 uuid = { version = "1", features = ["v4", "serde"] }
 
+# Secure storage (OS keyring/keychain)
+keyring = "3"
+