Plugins: Move lang() to Adminer\Plugin

adminer/include/plugin.inc.php

@@ -0,0 +1,16 @@
+<?php
+namespace Adminer;
+
+abstract class Plugin {
+	/** @var array<literal-string, string|list<string>>[] */ protected static $translations = array(); // key is language code
+
+	/** Translate a string from static::$translations; use Adminer\lang() for strings used by Adminer
+	* @param literal-string $idf
+	* @param float|string $number
+	*/
+	protected function lang(string $idf, $number = null) {
+		$args = func_get_args();
+		$args[0] = idx(static::$translations[LANG], $idf) ?: $idf;
+		return call_user_func_array('Adminer\lang_format', $args);
+	}
+}