fix: set global \$config stub so smiley_text() does not fatal in unit tests

After fixing global \$user, smiley_text() now fatals on \$config['allow_smilies']
because global \$config is also null in unit test context.  Set allow_smilies=0
so smiley_text() returns early without touching \$user->optionget() at all.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: avandenberghe

tests/core/recenttopics_events_test.php

@@ -318,9 +318,11 @@ private function make_rt_for_fill_template_events(\phpbb\event\dispatcher_interf
 		// global to our test dispatcher so that call does not fatal.
 		$GLOBALS['phpbb_dispatcher'] = $dispatcher;
 
-		// phpBB's real censor_text() → smiley_text() reads global $user and
-		// calls $user->optionget().  Point it at the same user mock.
-		$GLOBALS['user'] = $this->make_user_stub();
+		// phpBB's real censor_text() → smiley_text() reads global $config and
+		// $user.  Set both so neither access fatals in unit test context.
+		// allow_smilies=0 short-circuits smiley_text() before optionget() runs.
+		$GLOBALS['config'] = ['allow_smilies' => 0];
+		$GLOBALS['user']   = $this->make_user_stub();
 
 		return $rt;
 	}
@@ -645,7 +647,8 @@ public function test_modify_topictitle_prefix_is_applied_to_template_var()
 		$this->set_private($rt, 'total_topics_limit', 100);
 
 		$GLOBALS['phpbb_dispatcher'] = $dispatcher;
-		$GLOBALS['user'] = $this->make_user_stub();
+		$GLOBALS['config'] = ['allow_smilies' => 0];
+		$GLOBALS['user']   = $this->make_user_stub();
 
 		$this->call_private($rt, 'fill_template', ['recent_topics', [], 1]);
 
@@ -773,7 +776,8 @@ public function test_modify_tpl_ary_added_key_reaches_template()
 		$this->set_private($rt, 'total_topics_limit', 100);
 
 		$GLOBALS['phpbb_dispatcher'] = $dispatcher;
-		$GLOBALS['user'] = $this->make_user_stub();
+		$GLOBALS['config'] = ['allow_smilies' => 0];
+		$GLOBALS['user']   = $this->make_user_stub();
 
 		$this->call_private($rt, 'fill_template', ['recent_topics', [], 1]);