Laravel Nova Nested Form Versions Save

Fix #130

https://github.com/yassipad/laravel-nova-nested-form/pull/121 https://github.com/yassipad/laravel-nova-nested-form/pull/122 https://github.com/yassipad/laravel-nova-nested-form/pull/123

#120

Include latest PRs.

fixed: add initial field in create mode.

Fix syntax error preventing package use.

• Entire rewrite of the package
• Deprecate afterFill and beforeFill
• Add conditional display of the nested form
• Add support for polymorphic relations
• Add better support for files
• Updated design using the new Nova Panels

• apply #41 patch for nested relations asking parent required fields.
• add new method to check the current Nova version
• make methods compatible with both Nova 1 & 2 (e.g. $relation->getForeignKeyName())