feat(web): add CLI output message block support with layout improvements

Implement CLI output message type for displaying command output from user/assistant messages. Adds CliOutputBlock component and type with detection logic based on message metadata and CLI tags. Includes merging of adjacent CLI output blocks for cleaner presentation. Enhance layout throughout components with proper overflow handling and width constraints for improved text wrapping and scrolling behavior.

web/src/components/AssistantChat/HappyThread.tsx

@@ -32,8 +32,8 @@ export function HappyThread(props: {
             onRetryMessage: props.onRetryMessage
         }}>
             <ThreadPrimitive.Root className="flex min-h-0 flex-1 flex-col">
-                <ThreadPrimitive.Viewport className="min-h-0 flex-1 overflow-y-auto" autoScroll={false}>
-                    <div className="mx-auto w-full max-w-[720px] p-3">
+                <ThreadPrimitive.Viewport className="min-h-0 flex-1 overflow-y-auto overflow-x-hidden" autoScroll={false}>
+                    <div className="mx-auto w-full max-w-[720px] min-w-0 p-3">
                         {props.header}
                         <div className="flex flex-col gap-3">
                             <ThreadPrimitive.Messages components={THREAD_MESSAGE_COMPONENTS} />