Extract source api from app module (#8014)

* Extract source api from app module

* Extract source online api from app module

source-api/src/main/java/eu/kanade/tachiyomi/util/JsoupExtensions.kt

@@ -0,0 +1,26 @@
+package eu.kanade.tachiyomi.util
+
+import okhttp3.Response
+import org.jsoup.Jsoup
+import org.jsoup.nodes.Document
+import org.jsoup.nodes.Element
+
+fun Element.selectText(css: String, defaultValue: String? = null): String? {
+    return select(css).first()?.text() ?: defaultValue
+}
+
+fun Element.selectInt(css: String, defaultValue: Int = 0): Int {
+    return select(css).first()?.text()?.toInt() ?: defaultValue
+}
+
+fun Element.attrOrText(css: String): String {
+    return if (css != "text") attr(css) else text()
+}
+
+/**
+ * Returns a Jsoup document for this response.
+ * @param html the body of the response. Use only if the body was read before calling this method.
+ */
+fun Response.asJsoup(html: String? = null): Document {
+    return Jsoup.parse(html ?: body.string(), request.url.toString())
+}