Fix phpdoc QueryCache::class, SchemaCache::class. (#433)

* Fix phpdoc `QueryCache::class`, `SchemaCache::class`.

src/Cache/QueryCache.php

@@ -12,7 +12,19 @@
 use function is_array;
 
 /**
- * The cache application component that is used for query caching.
+ * QueryCache is a class provides a query cache feature for DB connections.
+ *
+ * The query cache allows you to cache the results of SELECT queries for a certain period of time. This can improve the
+ * performance of your application by avoiding the need to execute the same SELECT query multiple times.
+ *
+ * To use the query cache, you can configure a DB connection to use a QueryCache object as its query cache. When you
+ * execute a SELECT query using this connection, the query cache will check if the results of the query have been
+ * cached. If they have, it will return the cached results. If not, it will execute the query and cache the results
+ * before returning them.
+ *
+ * You can specify the lifetime of the cache using the {@see duration} property. You can also specify a cache
+ * dependency, which determines when the cache should be invalidated. For example, you can use a cache dependency based
+ * on the modification time of a table, so that the cache is invalidated whenever the table is updated.
  */
 final class QueryCache
 {
@@ -25,15 +37,15 @@ public function __construct(private CacheInterface $cache)
     }
 
     /**
-     * Return number of seconds that query results can remain valid in cache.
+     * @return int|null The number of seconds that query results can remain valid in cache.
      */
     public function getDuration(): int|null
     {
         return $this->duration;
     }
 
     /**
-     * Return true if QueryCache is active.
+     * @return bool True if QueryCache is active.
      */
     public function isEnabled(): bool
     {

src/Cache/SchemaCache.php

@@ -10,7 +10,14 @@
 use Yiisoft\Cache\Dependency\TagDependency;
 
 /**
- * The cache application component that is used to cache the table metadata.
+ * The SchemaCache class is used to cache database schema information.
+ *
+ * The Schema class retrieves information about the database schema from the database server and stores it in the cache
+ * for faster access. When the Schema class needs to retrieve information about the database schema, it first checks the
+ * cache using the SchemaCache class. If the information is not in the cache, the Schema class retrieves it from the
+ * database server and stores it in the cache using the SchemaCache class.
+ *
+ * SchemaCache is used by {@see \Yiisoft\Db\Schema\Schema} to cache table metadata.
  */
 final class SchemaCache
 {
@@ -57,17 +64,17 @@ public function set(
     }
 
     /**
-     * Return number of seconds that table metadata can remain valid in cache.
+     * @return int|null The number of seconds that table metadata can remain valid in cache.
      */
     public function getDuration(): int|null
     {
         return $this->duration;
     }
 
     /**
-     * Return true if the table is excluded from cache the table metadata.
-     *
      * @param string $value The table name.
+     *
+     * @return bool Whether the table is excluded from caching.
      */
     public function isExcluded(string $value): bool
     {