Allow Collections in AbstractPaginator::appends

[hctorres02]

Current behavior
In Illuminate\Pagination\AbstractPaginator, the appends method only accepts arrays or key/value pairs when adding query string values. Passing an Illuminate\Support\Collection is not supported unless it is explicitly converted to an array.

Post::paginate()->appends($collection); // Not supported

Why this matters

• Developer experience: avoids the need to manually call ->toArray() every time.
• Consistency: many Laravel APIs allow both arrays and collections interchangeably.
• Non-breaking: existing array and string usage remains unchanged.

Proposed solution
Update the conditional check in AbstractPaginator::appends to allow collections:

if (is_array($key) || $key instanceof \Illuminate\Support\Collection) {
    return $this->appendArray($key);
}