refactor: move extractPageTitleFromURL to module, add tests

src/content/utils/url.ts

@@ -0,0 +1,8 @@
+export function extractPageTitleFromURL(url: string): string {
+	var split = url.substring(url.indexOf("/wiki/") + "/wiki/".length);
+	if (split.indexOf('/') != -1) {
+		// Remove language suffix (/es)
+		split = split.substring(0, split.indexOf('/'));
+	}
+	return decodeURIComponent(split.replaceAll('_', ' '));
+}