refactor(supernova): refactor localItems, client.js, serviceApi, and processingStatus to use React Query

[TilmanHaupt]

Summary

Closes #681

Changes Made

• Introduced partially Optimistic Updates
• Deleted duplicates in the state (itemsByState, itemsByHash)
• Replaced localItem logic with React Query mutations and refetching.
• Removed obsolete constants associated with localItem and silence states.
• Deleted client.js, AltertmangerAPI, scheduledSilencesWrapper and apiService, as their responsibilities have been migrated to React Query or other parts of the code.
• Updated modal handling to ensure they close where appropriate, streamlining user interactions.
• This refactor simplifies state management, reduces redundancy, and leverages React Query’s capabilities for a cleaner, more maintainable codebase.

Testing Instructions

1. npm i
2. npm run TASK

Checklist

• I have performed a self-review of my code.
• I have commented my code, particularly in hard-to-understand areas.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• I have made corresponding changes to the documentation (if applicable).
• My changes generate no new warnings or errors.

[changeset-bot]

🦋 Changeset detected

Latest commit: df3ade6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@cloudoperators/juno-app-supernova	Minor

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[github-actions]

PR Preview Action v1.4.8
🚀 Deployed preview to https://cloudoperators.github.io/juno/pr-preview/pr-680/
on branch gh-pages at 2024-12-19 11:35 UTC

[ArtieReus]

This refactoring looks promising! Thank you! I’ve tested the UI despite the broken UI components, and I’d like to share my initial findings:

• The alerts list only displays active alerts.
• When silencing an alert from the alerts list, a success message is shown. However, the alert disappears from the list immediately, making it unclear whether the alert was successfully silenced, as it is no longer displayed.

[barsukov]

Great job, a lot of code deleted more clear way. Few comments from my side 🥇