test(aot): 添加AOT编译相关测试用例

- 添加对象克隆功能测试，验证clone关键字的正确性
- 添加复合赋值运算符测试，覆盖数组、对象属性等场景
- 添加exit/die语言结构测试，验证程序退出行为
- 添加嵌套闭包功能测试，验证闭包作用域和链式调用

tests/aot/clone.phpt

@@ -0,0 +1,35 @@
+--TEST--
+Clone keyword for object cloning
+--FILE--
+<?php
+
+class Counter {
+    public int $value;
+
+    public function __construct(int $v) {
+        $this->value = $v;
+    }
+
+    public function increment(): void {
+        $this->value++;
+    }
+}
+
+function main() {
+    $original = new Counter(10);
+    $original->increment();
+
+    $cloned = clone $original;
+    $cloned->increment();
+    $cloned->increment();
+
+    var_dump($original->value);
+    var_dump($cloned->value);
+    var_dump($original->value !== $cloned->value);
+}
+
+?>
+--EXPECT--
+int(11)
+int(13)
+bool(true)

tests/aot/compound-assign.phpt

@@ -0,0 +1,62 @@
+--TEST--
+Compound assignment in expressions
+--FILE--
+<?php
+
+class Counter {
+    public int $val = 0;
+}
+
+function main() {
+    // Array dim fetch with assignment operators
+    $arr = [1, 2, 3];
+    $arr[0] += 10;
+    $arr[1] *= 3;
+    $arr[2] -= 1;
+    var_dump($arr);
+
+    // Property with assignment operators
+    $obj = new Counter();
+    $obj->val += 5;
+    $obj->val *= 2;
+    $obj->val -= 3;
+    $obj->val %= 4;
+    var_dump($obj->val);
+
+    // Chained assignments
+    $a = $b = $c = 10;
+    var_dump($a);
+    var_dump($b);
+    var_dump($c);
+
+    // Reference assignment
+    $y = 2;
+    $z = &$y;
+    $y = 5;
+    var_dump($z);
+
+    // Global variable with assignment
+    global $config;
+    $config = ["debug" => true];
+    var_dump($config["debug"]);
+
+    echo "done\n";
+}
+
+?>
+--EXPECT--
+array(3) {
+  [0]=>
+  int(11)
+  [1]=>
+  int(6)
+  [2]=>
+  int(2)
+}
+int(3)
+int(10)
+int(10)
+int(10)
+int(5)
+bool(true)
+done

tests/aot/exit-test.phpt

@@ -0,0 +1,35 @@
+--TEST--
+exit/die language constructs
+--FILE--
+<?php
+
+function testExit(int $code): void {
+    if ($code > 0) {
+        echo "should not reach here\n";
+    }
+    echo "code is zero\n";
+}
+
+function processValue(mixed $val): string {
+    if (!is_string($val)) {
+        die("not a string");
+    }
+    return "string: " . $val;
+}
+
+function main() {
+    testExit(0);
+
+    $result = processValue("hello");
+    var_dump($result);
+
+    $status = 42;
+    $x = $status == 0 ? 'zero' : 'non-zero';
+    var_dump($x);
+}
+
+?>
+--EXPECT--
+code is zero
+string(13) "string: hello"
+string(8) "non-zero"

tests/aot/nested-closures.phpt

@@ -0,0 +1,56 @@
+--TEST--
+Nested closures and closure scope
+--FILE--
+<?php
+
+function makeMultiplier(int $factor): Closure {
+    return function (int $value) use ($factor): int {
+        return $value * $factor;
+    };
+}
+
+function makeAdder(int $base): Closure {
+    return function (int $value) use ($base): int {
+        return $value + $base;
+    };
+}
+
+function makeFormatter(string $prefix): Closure {
+    return function (string $name) use ($prefix): string {
+        return $prefix . ": " . $name;
+    };
+}
+
+function makeChain(int $x): Closure {
+    return function (int $y) use ($x): Closure {
+        return function (int $z) use ($x, $y): int {
+            return $x + $y + $z;
+        };
+    };
+}
+
+function main() {
+    $double = makeMultiplier(2);
+    $add5 = makeAdder(5);
+
+    var_dump($double(10));
+    var_dump($add5(10));
+
+    $result = $add5($double(3));
+    var_dump($result);
+
+    $format = makeFormatter("User");
+    var_dump($format("Alice"));
+
+    $chain = makeChain(1);
+    $chain2 = $chain(2);
+    var_dump($chain2(3));
+}
+
+?>
+--EXPECT--
+int(20)
+int(15)
+int(11)
+string(11) "User: Alice"
+int(6)