[Drag&Drop] Add stopPropagation to DropZone

[MarvinKlein1508]

Pull Request

📖 Description

This PR adds stopPropagation to the FluentDropZone component. This allows the component to be used in nested FluentDragContainer components.

@ondrop:stopPropagation
@ondragenter:stopPropagation
@ondragend:stopPropagation
@ondragover:stopPropagation
@ondragleave:stopPropagation
@ondragstart:stopPropagation

🎫 Issues

This PR fixes #3925

👩‍💻 Reviewer Notes

@dvoituron I'm not sure if I can always set stopPropagation. I've seen that you do this for preventDeafult based on Droppable. But I couldn't find any downside in adding this attribute.

📑 Test Plan

✅ Checklist

General

• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I have read the CONTRIBUTING documentation and followed the standards for this project.

Component-specific

• I have added a new component
• I have added Unit Tests for my new component
• I have modified an existing component
• I have validated the Unit Tests for an existing component

⏭ Next Steps

I've got a working demo with three nested FluentDragContainers which I prepare for PR as well. Still optimizing styling. Here is a sneak peak:
https://github.com/user-attachments/assets/5c5eefe0-1eb7-4e37-93f0-7ce5f9775cb6

[dvoituron]

@MarvinKlein1508

Why not add a parameter like we did in FluentButton? That way, the developer can decide when to use it.
I should use a single parameter for all these attributes.

/// <summary>
/// Gets or sets a way to prevent further propagation of the current event in the capturing and bubbling phases.
/// </summary>
[Parameter]
public bool StopPropagation { get; set; } = false;

[MarvinKlein1508]

Why not add a parameter like we did in FluentButton? That way, the developer can decide when to use it. I should use a single parameter for all these attributes.

Good call! I will adjust the PR early tomorrow.

[MarvinKlein1508]

Done. I've also added a test for the new parameter.