Support for Repeating Groups with Inline Add/Edit

[signalwerk]

It would be extremely useful if Manifest supported "repeating groups" (In Decap/Netlify CMS also called Nested Collections) – a way to add multiple items or even combinations of fields within a single entity. For example, instead of having a single image field, users could define a repeating group (e.g., "gallery") that allows them to add multiple images along with additional details like captions and alt text. Ideally, this group would support inline add/edit functionality, so users can manage each item directly within the parent entity view. This feature would simplify data modelling for scenarios where multiple entries are required without the overhead of creating separate entities for each instance.

Here a visual representation of how I imagine this:

+----------------------------------------------+
| Editor                                       |
+----------------------------------------------+
| Title:    [________________________]         |
| Summary:  [________________________]         |
|           +-------------------------------+  |
|  Gallery: | (Repeating Group)             |  |
|           +-------------------------------+  |
|           [Image]  Caption: [___________] |  |
|           [Image]  Caption: [___________] |  |
|           [Image]  Caption: [___________] |  |
|           [ Add new Image ]               |  |
|           +-------------------------------+  |
|                                              |
|           +-------------------------------+  |
|  URLs:    | (Repeating Group)             |  |
|           +-------------------------------+  |
|           URL: [___________]              |  |
|           URL: [___________]              |  |
|           URL: [___________]              |  |
|           [ Add new URL ]                 |  |
|           +-------------------------------+  |
|                                              |
+----------------------------------------------+

The definition of the property could be like:

- name: gallery
  type: group
  multiple: true
  fields:
    - { name: image, type: image }
    - { name: caption, type: string }
- name: urls
  type: group
  multiple: true
  fields:
    - { name: url, type: link }

behind the scene and in the API it would work exaclty like a belongsToMany relation. Only that the collection would not be visible to the user under collection (no edit out of context of the «parent»-entity). So for the database-table editor there would be editor_gallery and editor_urls.

[brunobuddy]

@signalwerk this is really cool. I saw that on Strapi and I found that really useful.