feat(openclaw): add provider form fields and UI components

- Add OpenClawFormFields component for provider configuration
- Add Collapsible UI component (radix-ui dependency)
- Update ProviderForm with OpenClaw-specific handlers and preset logic
- Extend OpenClawModel type with reasoning, input, maxTokens fields
- Exclude OpenClaw from universal provider tab in AddProviderDialog

src/components/ui/collapsible.tsx

@@ -0,0 +1,9 @@
+import * as CollapsiblePrimitive from "@radix-ui/react-collapsible"
+
+const Collapsible = CollapsiblePrimitive.Root
+
+const CollapsibleTrigger = CollapsiblePrimitive.CollapsibleTrigger
+
+const CollapsibleContent = CollapsiblePrimitive.CollapsibleContent
+
+export { Collapsible, CollapsibleTrigger, CollapsibleContent }