fix(i18n): localize statistics page and troops Hero label [#197]

On a fresh install several strings were still hardcoded in English
(reported on the live server, RO locale):

- statistiken.php: the page <title>, the <h1> and the tab bar
  (Player / Alliances / Villages / Heroes / General) were literal English.
- Templates/Ranking/ranksearch.tpl: the "back | forward" pagination links.
- Templates/troops.tpl: the "Hero" troop-row label.

Wire them to language constants. Reuse existing ones
(STATISTICS, PLAYER, PLAYERS, VILLAGES, BACK, FORWARD, U0) and add three
new constants (ALLIANCES, HEROES, GENERAL) to en/fr/ro. WW is kept as-is
(universal acronym).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

GameEngine/Lang/en.php

@@ -780,6 +780,9 @@ tz_def('AND', 'and');
 //other
 tz_def('VILLAGE', 'Village');
 tz_def('STATISTICS', 'Statistics');
+tz_def('ALLIANCES', 'Alliances');
+tz_def('HEROES', 'Heroes');
+tz_def('GENERAL', 'General');
 tz_def('OASIS', 'Oasis');
 tz_def('NO_OASIS', 'You do not own any oases.');
 tz_def('NO_VILLAGES', 'There are no villages.');

GameEngine/Lang/fr.php

@@ -776,6 +776,9 @@ define('AND', 'et');
 //other
 define('VILLAGE', 'Village');
 define('STATISTICS', 'Statistiques');
+define('ALLIANCES', 'Alliances');
+define('HEROES', 'Héros');
+define('GENERAL', 'Général');
 define('OASIS', 'Oasis');
 define('NO_OASIS', 'Vous ne possédez aucune oasis.');
 define('NO_VILLAGES', 'Il n\'y a pas de villages.');

GameEngine/Lang/ro.php

@@ -776,6 +776,9 @@ define('AND', 'și');
 //other
 define('VILLAGE', 'Sat');
 define('STATISTICS', 'Statistici');
+define('ALLIANCES', 'Alianțe');
+define('HEROES', 'Eroi');
+define('GENERAL', 'General');
 define('OASIS', 'Oază');
 define('NO_OASIS', 'Nu deții nicio oază.');
 define('NO_VILLAGES', 'Nu există sate.');