Add missing feature of the ModelFieldSelector popover :
* keyboard navigation
* additional debug value
* add default value page ( for dynamic placeholder)
* add validate callback
Migrate dynamic placeholder to be compatible with new OWL field.
task-2978722
X-original-commit: 929108e29168058fad5da85e0ff9c66d2c5b2525
Part-of: odoo/odoo#102603