feat(webui): refine output timeline and model controls (#4108)

* feat(webui): refine output timeline and composer queue

* feat(webui): add provider model picker

* fix(webui): polish model settings and heartbeat checks

* chore: keep heartbeat changes out of webui pr

* refactor(webui): isolate settings routes

* fix(providers): align minimax anthropic test

* fix(providers): keep minimax anthropic base sdk-compatible

* fix(providers): normalize anthropic base urls

webui/src/components/MarkdownText.tsx

@@ -40,6 +40,7 @@ const MemoizedMarkdownRenderer = memo(function MemoizedMarkdownRenderer({
 const SHORT_STREAM_COMMIT_MS = 80;
 const MEDIUM_STREAM_COMMIT_MS = 140;
 const LONG_STREAM_COMMIT_MS = 220;
+const STREAMING_HIGHLIGHT_CHAR_LIMIT = 16_000;
 
 export function preloadMarkdownText(): void {
   void loadMarkdownRenderer();
@@ -56,7 +57,9 @@ export function MarkdownText({
   streaming = false,
 }: MarkdownTextProps) {
   const renderedSource = useStreamingMarkdownSource(children, streaming);
-  const highlightCode = !streaming && renderedSource === children;
+  const highlightCode = streaming
+    ? renderedSource.length <= STREAMING_HIGHLIGHT_CHAR_LIMIT
+    : renderedSource === children;
 
   useEffect(() => {
     if (streaming) preloadMarkdownText();