minor #126 [PhpStan] Fix @template boundaries (ogizanagi)

This PR was merged into the 0.x-dev branch.

Discussion
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[PhpStan] Fix `@template` boundaries

See https://arnaud.le-blanc.net/post/phpstan-generics.html#bounds

With this, PhpStan properly detects the return type of `ContentManagerInterface::getContent(Foo::class, 'foo')` is of type `Foo` and not just `object`

Commits
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9f4184d [PhpStan] Fix `@template` boundaries

src/ContentManagerInterface.php

@@ -16,7 +16,7 @@ interface ContentManagerInterface
     /**
      * List all content for the given type
      *
-     * @template T
+     * @template T of object
      *
      * @param class-string<T>                  $type     Model FQCN e.g. "App/Model/Article"
      * @param string|array|callable            $sortBy   String, array or callable
@@ -31,7 +31,7 @@ public function getContents(string $type, $sortBy = null, $filterBy = null): arr
     /**
      * Fetch a specific content
      *
-     * @template T
+     * @template T of object
      *
      * @param class-string<T> $type Model FQCN e.g. "App/Model/Article"
      * @param string          $id   Unique identifier (slug)