fix(php): 修复作用域管理和类型转换问题

- 修正了 leaveScope 方法中的作用域级别递减顺序
- 将致命错误改为普通错误以处理浮点数到大整数的转换
- 使用严格相等比较修复数组变量检测逻辑

src/Php/Context/FunctionContext.php

@@ -96,7 +96,7 @@ class FunctionContext
 
     public function leaveScope(): void
     {
-        unset($this->scopeLayouts[$this->scopeLevel]);
         $this->scopeLevel--;
+        unset($this->scopeLayouts[$this->scopeLevel]);
     }
 }

src/Php/Parser/TypeConversionTrait.php

@@ -76,7 +76,7 @@ trait TypeConversionTrait
             return 'php::toBigInt(' . $this->trimBrackets($expr) . ')';
         }
         if ($fromType === self::TYPE_FLOAT) {
-            $this->fatalError(null, 'Cannot convert float to BigInt, use string or int instead');
+            $this->error('Cannot convert float to BigInt, use string or int instead');
         }
         if ($fromType === self::TYPE_STR) {
             return 'php::toBigInt(php::toString(' . $this->trimBrackets($expr) . '))';

src/Php/Parser/TypeDetectionTrait.php

@@ -138,7 +138,7 @@ trait TypeDetectionTrait
 
     protected function isArrayVar($var): bool
     {
-        return $this->isVarExpr($var) and $this->hasVar($var->name) and $this->getVarType($var->name) == self::TYPE_ARRAY;
+        return $this->isVarExpr($var) and $this->hasVar($var->name) and $this->getVarType($var->name) === self::TYPE_ARRAY;
     }
 
 }