feat(php): 添加对PHP枚举类型的支持

- 在ClassDef实体中添加enum属性用于标识枚举类
- 修改编译器基类以支持枚举常量访问的特殊处理
- 移除旧的枚举示例文件并添加新的测试用例
- 更新翻译器以识别和标记枚举类型的类定义

src/Php/CompilerBase.php

@@ -3203,6 +3203,10 @@ class CompilerBase extends \PhpAot\Core\Translator
                 if ($classDef->hasConstant($const)) {
                     return $classDef->getConstant($const)->value;
                 }
+                if ($classDef->enum) {
+                    $ce = $this->getClassEntryPtr($class);
+                    return 'php::getEnumCase(' . $ce . ', ' . $this->getLiteralString($const) . ')';
+                }
             }
             $ce = $this->getClassEntryPtr($class);
             return 'php::constant(' . $ce . ', ' . $this->getLiteralString($const) . ')';

src/Php/Entity/ClassDef.php

@@ -27,6 +27,7 @@ class ClassDef extends ClassLikeDef
     public array $implements = [];
     public string $extends = '';
     public bool $requireCtor = false;
+    public bool $enum = false;
     public int $flags;
 
     public function __construct(string $name, int $flags, string $namespace = '')

src/Php/Translator.php

@@ -660,7 +660,12 @@ class Translator extends Preprocessor
             $flags = $class->flags;
             $extends = $class->extends;
         }
+
         $this->classDef = new ClassDef($this->class, $flags, $this->namespace);
+        if ($class instanceof Node\Stmt\Enum_) {
+            $this->classDef->enum = true;
+        }
+
         if ($extends) {
             $this->classDef->extends = $this->parseIdentifier($class->extends);
             if (isset($this->classes[$this->classDef->extends])) {

tests/aot/enum1.phpt

@@ -1,3 +1,6 @@
+--TEST--
+enum 2
+--FILE--
 <?php
 interface Colorful {
     public function color(): string;
@@ -24,3 +27,9 @@ function main()
     echo Suit::Clubs->color() . "\n";
     echo Suit::Spades->color() . "\n";
 }
+?>
+--EXPECT--
+Red
+Red
+Black
+Black