fix(panel): thread scroller opts out of scroll anchoring

ui/src/lib/panel/chat-view.svelte

@@ -37,7 +37,6 @@
   let loadedAt = $state(new Date(0).toISOString());
   let scroller = $state<HTMLDivElement | null>(null);
   let body = $state<HTMLDivElement | null>(null);
-  let end = $state<HTMLDivElement | null>(null);
   const SETTLE_MS = 2500;
   const SETTLE_STEP_MS = 120;
   let settleUntil = 0;
@@ -90,7 +89,6 @@
     if (scroller) {
       scroller.scrollTop = 0;
     }
-    end?.scrollIntoView({ block: "end" });
   }
 
   async function scrollToBottom() {
@@ -208,7 +206,7 @@
 </script>
 
 <div
-  class="flex min-h-0 flex-1 flex-col-reverse overflow-y-auto overflow-x-hidden px-3 py-3 @md:px-6"
+  class="flex min-h-0 flex-1 flex-col-reverse overflow-y-auto overflow-x-hidden px-3 py-3 [overflow-anchor:none] @md:px-6"
   onscroll={() => {
     if (Date.now() > settleUntil) {
       pinned = nearBottom();
@@ -341,6 +339,5 @@
     {#each tail as turn (turn.id)}
       <TurnCard {now} {turn} />
     {/each}
-    <div aria-hidden="true" class="h-px shrink-0" bind:this={end}></div>
   </div>
 </div>