Add test coverage for static property access patterns in array offset checks

Covers array_key_first, array_key_last, array_rand, and count()-1
special cases with static properties, as requested in review.

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

Author: 2 people

tests/PHPStan/Rules/Arrays/data/bug-14390.php

@@ -92,3 +92,40 @@ public function countMinus1Property(
 		}
 	}
 }
+
+class StaticProps
+{
+	/** @var array<string, string> */
+	public static array $fields = [];
+
+	/** @var list<string> */
+	public static array $items = [];
+
+	public function arrayKeyFirstStatic(): void
+	{
+		if (self::$fields !== []) {
+			echo self::$fields[array_key_first(self::$fields)];
+		}
+	}
+
+	public function arrayKeyLastStatic(): void
+	{
+		if (self::$fields !== []) {
+			echo self::$fields[array_key_last(self::$fields)];
+		}
+	}
+
+	public function arrayRandStatic(): void
+	{
+		if (self::$fields !== []) {
+			echo self::$fields[array_rand(self::$fields)];
+		}
+	}
+
+	public function countMinus1Static(): void
+	{
+		if (self::$items !== []) {
+			echo self::$items[count(self::$items) - 1];
+		}
+	}
+}