lyngweb: refactor SiteHighlight to align package structure and add adjustable textarea height

site/src/jsMain/kotlin/TryLyngPage.kt

@@ -145,7 +145,9 @@ fun TryLyngPage() {
                         ev.preventDefault()
                         runCode()
                     }
-                }
+                },
+                // Keep current initial size but allow the editor to grow with content
+                autoGrow = true
             )
         }
 

site/src/jsTest/kotlin/HighlightSmokeTest.kt

@@ -20,6 +20,7 @@ package net.sergeych.site
 import net.sergeych.lyng.highlight.HighlightKind
 import net.sergeych.lyng.highlight.HighlightSpan
 import net.sergeych.lyng.highlight.SimpleLyngHighlighter
+import net.sergeych.lyngweb.SiteHighlight
 import kotlin.test.Test
 import kotlin.test.assertContains
 import kotlin.test.assertTrue