feat(Actions): re-implemented action with new UI

[framitdavid]

Description

This PR has refactored the user interface for how actions are handled in the process editor. Additionally, a new class called BpmnActionModeler has been added to create a simpler interface between the process editor and the bpmnjs package. (I had a meeting with the team to present the proposal before creating this pull request).

Related Issue(s)

• 12835

Verification

• [x] Your code builds clean without any errors or warnings
• [x] Manual testing done (required)
• [x] Relevant automated test added (if you find this hard, leave it and we'll help out) (I did leave the ActionModeler out of tests, due to heavy mocking of bpmnjs.)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 83.95722% with 30 lines in your changes missing coverage. Please review.

Project coverage is 91.69%. Comparing base (f2657c2) to head (d0576a8). Report is 2 commits behind head on main.

:exclamation: Current head d0576a8 differs from pull request most recent head 31d3cb4

Please upload reports for the commit 31d3cb4 to get more accurate results.

Files	Patch %	Lines
...process-editor/src/utils/bpmn/BpmnActionModeler.ts	21.87%	25 Missing :warning:
...ges/process-editor/src/utils/bpmn/StudioModeler.ts	60.00%	4 Missing :warning:
...ontent/EditActions/ActionsEditor/ActionsEditor.tsx	96.15%	0 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #12982 +/- ## ========================================== - Coverage 91.80% 91.69% -0.11% ========================================== Files 1402 1414 +12 Lines 19859 19927 +68 Branches 2390 2396 +6 ========================================== + Hits 18231 18273 +42 - Misses 1371 1397 +26 Partials 257 257 ```

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[framitdavid]

Some comments added 😄

Thanks! I have taken your feedback into account and changed due to your suggestions. It's all yours! 😎