fix(article): warm up large single-block articles

The warm-up ran only above a block-count threshold, so an article
that parses into one large block never qualified. Trigger on the
total character count as well.

app/src/main/java/com/example/research/ui/article/ArticleTextWarmUp.kt

@@ -13,11 +13,14 @@ import kotlinx.coroutines.currentCoroutineContext
 import kotlinx.coroutines.ensureActive
 
 internal const val HEAVY_ARTICLE_BLOCK_COUNT = 100
+internal const val HEAVY_ARTICLE_TOTAL_CHARS = 1_500
 
 object ArticleTextWarmUp {
 
     suspend fun warmUp(context: Context, blocks: List<DslBlock>) {
-        if (blocks.size <= HEAVY_ARTICLE_BLOCK_COUNT) return
+        if (blocks.size <= HEAVY_ARTICLE_BLOCK_COUNT &&
+            blocks.sumOf { it.text.length } <= HEAVY_ARTICLE_TOTAL_CHARS
+        ) return
         val density = Density(context)
         val measurer = TextMeasurer(
             defaultFontFamilyResolver = createFontFamilyResolver(context),