Improve assistant message action placement for split responses (#1032)

* Improve assistant message action placement for split responses

* Add toggle for split assistant message actions

* Address split message actions review feedback

* Fix inline assistant actions

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Co-authored-by: vhqtvn <8930337+vhqtvn@users.noreply.github.com>
Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/lib/desktop.ts

@@ -133,6 +133,7 @@ export type DesktopSettings = {
   mermaidRenderingMode?: 'svg' | 'ascii';
   userMessageRenderingMode?: 'markdown' | 'plain';
   stickyUserHeader?: boolean;
+  showSplitAssistantMessageActions?: boolean;
   fontSize?: number;
   terminalFontSize?: number;
   uiFont?: string;