Extend autolink parsing to handle non-HTTP links, add fallback for invalid autolinks, and update ParseTest coverage.

src/commonMain/kotlin/nl/astraeus/markdown/parser/Paragraph.kt

@@ -133,8 +133,12 @@ private val states = listOf(
 
     if (content.contains("@") and content.contains(".")) {
       Link("mailto:$content", content)
-    } else {
+    } else if (content.startsWith("http://") ||
+      content.startsWith("https://")
+    ) {
       Link(content, content)
+    } else {
+      Text("<$content>")
     }
   },