ace.js: search highlighting makes the editor unresponsive on large folded document

### Describe the bug

Search highlighting can make the editor very unresponsive when searching a large, heavily folded document.

### Expected Behavior

Editor should remain responsive independent of folded sections

### Current Behavior

Editor becomes unresponsive

### Reproduction Steps

1. Open: https://sekedus.github.io/ace/kitchen-sink.html
2. Paste the contents of test.xodr.xml
3. Fold a lot of high level `` elements (like 15-20)
4. Search for "Road" and scroll, the editor will be very unresponsive

[test.xodr.xml](https://github.com/user-attachments/files/30163372/test.xodr.xml)

### Possible Solution

_No response_

### Additional Information/Context

_No response_

### Ace Version / Browser / OS / Keyboard layout

v1.44.0 / Safari / Mac OS 26 / DE

Start by opening the kitchen-sink reproduction and loading the attached test.xodr.xml; fold 15–20 high-level elements, search for “Road,” and scroll to confirm the slowdown. Trace the search-highlighting and folded-document behavior from that reproduction, then verify that the editor remains responsive under the same steps.

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