feat: adds support to additional properties on material renderer

[lucasoares]

Fixes #2492

This is a draft PR initially generated with Copilot and then reworked manually.

I'm not familiar with the jsonforms codebase and don't have much time right now to dive deeply into it. I did a bit of work on top of what Copilot generated, but I didn’t spend too much time polishing it. The goal was mainly to provide a working version of additionalProperties rendering with the Material renderer.

Everything appears to be working: adding and removing data inside both the object and its arrays. That said, this was mostly an experiment to see if Copilot could handle the issue (I may end up using this version in a fork). For this to be production-ready, it will likely need to be redone properly using this as a reference. Since I have 0 context of jsonforms code, I couldn’t provide more detailed instructions for further development.

Schema example:

"propertiesArrayOfValuesByKey": {
  "type": "object",
  "title": "Array of Values by Key",
  "additionalProperties": {
    "type": "array",
    "items": {
      "type": "string"
    },
    "title": "Item"
  }
}

Rendered form:

All actions are working: you can add and remove data inside both the object and the arrays.

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[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ lucasoares
❌ Copilot
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[lucas-koehler]

@lucasoares Thanks a lot for your proposal!
Before we can consider any contribution, the CLA needs to be signed.
That said, we unfortunately don’t have the capacity to complete partially implemented community PRs.
If you’re able to provide a (mostly) complete implementation, we’d be happy to review it and provide feedback.

[lucasoares]

@lucasoares Thanks a lot for your proposal! Before we can consider any contribution, the CLA needs to be signed. That said, we unfortunately don’t have the capacity to complete partially implemented community PRs. If you’re able to provide a (mostly) complete implementation, we’d be happy to review it and provide feedback.

The code is essentially complete. it’s not a partial implementation for what I proposed to do. It represents the full feature, including basic tests and comprehensive examples that confirm it's working as intended.

When I mentioned it was an experiment, I meant that I'm not fully familiar with the JSONForms code structure and conventions so I had to use the copilot for the initial version, and I didn't have enough time to study them in detail to ensure full alignment. That said, the implementation works and I'm currently using it in my own product.

Regarding the CLA, I can't sign it on behalf of Copilot, but I have rebased the branch and signed it myself if you'd like to move forward with the PR.

I'm happy to make any adjustments needed to align the code with the JSONForms codebase and style guidelines.

[lucas-koehler]

@lucasoares I see that is fine then. I think I misunderstood. The CLA is still shown as incomplete though. I think you need to open a new PR with a squashed commit that is authored by you.