Fix compression reference card anchoring

static/ui.js

@@ -5562,7 +5562,7 @@ function renderMessages(options){
       const turn=anchorSeg.closest('.assistant-turn');
       const blocks=_assistantTurnBlocks(turn);
       if(blocks){
-        blocks.appendChild(node);
+        blocks.insertBefore(node, anchorSeg);
         return;
       }
       const turnParent=turn && turn.parentElement;

tests/test_auto_compression_card.py

@@ -274,6 +274,19 @@ def test_reference_message_uses_raw_transcript_position_before_anchor_fallback()
     assert "else _insertCompressionLikeNode(referenceNode);" in src
 
 
+def test_reference_message_inserted_before_future_assistant_anchor():
+    src = _read("static/ui.js")
+    start = src.find("function _insertCompressionLikeNodeByRawIdx")
+    assert start != -1, "raw-index insertion helper not found"
+    end = src.find("const preservedOnlyNode", start)
+    assert end != -1, "raw-index insertion helper end marker not found"
+    helper = src[start:end]
+
+    assert "const anchorSeg=assistantSegments.get(anchorRawIdx);" in helper
+    assert "blocks.insertBefore(node, anchorSeg);" in helper
+    assert helper.index("blocks.insertBefore(node, anchorSeg);") < helper.index("const userRow=userRows.get(anchorRawIdx);")
+
+
 def test_reference_message_selection_prefers_latest_matching_marker():
     src = _read("static/ui.js")
     start = src.find("function _latestCompressionReferenceMessage")