perf: skip re-splitting unchanged text tokens

Author: Algorithm5838

src/lib/components/chat/Messages/Markdown/MarkdownInlineTokens/TextToken.svelte

@@ -1,12 +1,14 @@
 <script lang="ts">
 	export let token;
 	export let done = true;
+
+	$: raw = token?.raw ?? '';
 </script>
 
 {#if done}
-	{token?.raw}
+	{raw}
 {:else}
-	{#each (token?.raw ?? '').split(' ') as text}
+	{#each raw.split(' ') as text}
 		<span class="fade-in-token">
 			{text}{' '}
 		</span>