Fix/modal callback in modal callback

[ibelar]

This will properly allow to use modal callback inside another modal callback.

For example, allow to display a table in a modal using an action column edit that open another modal using a form.

$t = $app->add('Table');
$m = $t->setModel($m);

$t->addColumn(null, 'Actions')->addModal('btn', 'Title', function ($modal, $id) use ($m, $app) {
    // get this app.
    $m->load($id);

    $modal->add(['Header', $mUserApps['name'], 'size' => 4]);

    $table = $modal->add('Table');
    $table->setModel(new Model());

    $table->addColumn(null, 'Actions')->addModal('Edit Item', 'Editing item', function($editModal, $id) use ($m) {
        $f = $editModal->add('Form');
        $f->setModel($m)->load($id));
        $f->onSubmit(function($f) use ($modal, $editModal, $tablePerm) {
           $f->model->save();
           return [$editModal->owner->hide(), new jsReload($table)];
        });
    });
});

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@9964bc8). Click here to learn what that means.
The diff coverage is 25%.

@@            Coverage Diff             @@
##             develop     #509   +/-   ##
==========================================
  Coverage           ?   65.74%           
  Complexity         ?     1572           
==========================================
  Files              ?       88           
  Lines              ?     3757           
  Branches           ?        0           
==========================================
  Hits               ?     2470           
  Misses             ?     1287           
  Partials           ?        0

Impacted Files	Coverage Δ	Complexity Δ
src/Modal.php	40.47% <25%> (ø)	37 <0> (?)

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