insert_model_entry does not accept true for boolean fields

[nickcernis]

insert_model_entry only updates boolean values to true if 'on' is passed in place of true.

To reproduce

1. Create a model called 'rabbit' with a boolean field named 'bool'.
2. Run this code:

    $model_id   = 'rabbit';
    $field_data = [
  	  'bool'  => true,						
    ];	

    $post_id = insert_model_entry( $model_id, $field_data );

    var_dump( $post_id );     

3. Grab the post meta for the new post ID via wp post meta list [id-of-post]
4. The bool value will be false/'off' instead of the expected true/'on'.

Repeat the same with a value of 'on' and post meta should save correctly.

Expected behavior

Boolean values passed for boolean fields should save.

Version information

• Plugin version: 0.19.2
• WordPress version: 6.0.1

Additional context

From the report in Slack:

l believe there's a bug in how boolean values are being evaluated in the /plugins/atlas-content-modeler/includes/publisher/lib/field-functions.php file. It should be checking for true/false on line 327. Instead it checks for "on" and booleans are never set as true in the model.

Relevant lines (perhaps check for true or 'on' instead of just 'on', or migrate to real boolean values):

atlas-content-modeler/includes/publisher/lib/field-functions.php

Lines 326 to 327 in 8a2c543

	case 'boolean':
	return $value === 'on' ? 'on' : 'off';

Workaround

Boolean field values have to be cast as 'on' or 'off':

	$model_id   = 'rabbit';
	$boolean_value = true;
	$field_data = [		
		'bool' => $boolean_value ? 'on' : 'off',
	];	

	$post_id = insert_model_entry( $model_id, $field_data );