[CodeQuality] Split ExplicitBoolCompareRector into array and object variants

[TomasVotruba]

Splits ExplicitBoolCompareRector into three focused rules, so array and object explicit-bool comparisons can be enabled or skipped independently.

ExplicitBoolCompareRector no longer touches array or object conditions; it now explicitly skips them, and the two new rules own those cases. The CodeQualityLevel keeps the same overall coverage, with the new rules ordered before the original so they run first.

Rule	Handles
ArrayExplicitBoolCompareRector (new)	array-type variable
ObjectExplicitBoolCompareRector (new)	nullable object
ExplicitBoolCompareRector (narrowed)	count(), string, int, float

ArrayExplicitBoolCompareRector

 public function run(array $items)
 {
-    if (!$items) {
+    if ($items === []) {
         return 'no items';
     }
 }

ObjectExplicitBoolCompareRector

 public function run(?\stdClass $item)
 {
-    if (!$item) {
+    if (!$item instanceof \stdClass) {
         return 'empty';
     }
 }

ExplicitBoolCompareRector

 public function run($items)
 {
-    if (!count($items)) {
+    if (count($items) === 0) {
         return 'no items';
     }
 }