fix(sonar): use nullish coalescing assignment

[etzel-mes]

Description

Replace five conditional nullish initialization patterns with the nullish coalescing assignment operator, addressing Sonar rule typescript:S6606 while preserving existing behavior.

Closes #3737

Type of Change

• Bug fix
• New feature
• Improvement
• Documentation update
• Other

How Has This Been Tested?

• Focused tests for BeansEntityHandler, PipeErrorHandlerPage, EventNotifier, ExtensionRegistry, and NodeNamespaceContext — 45 tests passed
• yarn workspace @kaoto/kaoto lint
• yarn workspace @kaoto/kaoto lint:style

Checklist

• I have read the Contributing Guidelines.
• I have followed the coding style and conventions of the project.
• I have tested my changes and ensured that they work as expected.
• Documentation update — not applicable to this code-quality cleanup.
• New tests — existing focused tests cover the unchanged initialization behavior.

AI assistance was used. The change was reviewed and approved by the human operator before submission.

Summary by CodeRabbit

• Refactor
  • Streamlined internal initialization logic across visualization, error handling, event notification, XML deserialization, and namespace processing.
  • Preserved existing behavior while making lazy creation and caching more concise and consistent.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 8035568c-13f7-4f09-bea4-c72ba7962ec1

📥 Commits

Reviewing files that changed from the base of the PR and between c07cde3 and 4ac2ddd.

📒 Files selected for processing (5)

• packages/ui/src/models/visualization/metadata/beans-entity-handler.ts
• packages/ui/src/pages/PipeErrorHandler/PipeErrorHandlerPage.tsx
• packages/ui/src/utils/event-notifier.ts
• packages/ui/src/xml-schema-ts/extensions/DefaultExtensionDeserializer.ts
• packages/ui/src/xml-schema-ts/utils/NodeNamespaceContext.ts

Included review availability: Your plan provides up to 2 included reviews per hour; 1 remains after this review.

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📝 Walkthrough

Walkthrough

The changes replace five explicit null-check initialization blocks with the ??= operator. The affected code covers beans entities, pipe error handler entities, the event notifier singleton, extension metadata maps, and namespace prefix caches.

Changes

Nullish assignment cleanup

Layer / File(s)	Summary
Replace conditional initialization packages/ui/src/models/visualization/metadata/beans-entity-handler.ts, packages/ui/src/pages/PipeErrorHandler/PipeErrorHandlerPage.tsx, packages/ui/src/utils/event-notifier.ts, packages/ui/src/xml-schema-ts/extensions/DefaultExtensionDeserializer.ts, packages/ui/src/xml-schema-ts/utils/NodeNamespaceContext.ts	Five explicit initialization guards now use nullish coalescing assignment. Existing initialization behavior remains unchanged.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 4ac2d

This is a localized code-quality cleanup that preserves existing lazy-initialization behavior, with no actionable merge-blocking risk remaining after normal checks and review.

Suggested reviewers: lhein

Poem

A rabbit spots five guards in line
And swaps each one for ??= shine
The caches wake when values flee
The singleton stays lazily
Clean code hops through every vine

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the main change: replacing conditional initialization with nullish coalescing assignment to address Sonar.
Linked Issues check	✅ Passed	The PR updates all five files listed in issue #3737 and replaces the specified conditional initialization patterns with ??= while preserving behavior.
Out of Scope Changes check	✅ Passed	The changes are limited to the five files and the nullish initialization refactoring required by issue #3737. No unrelated changes are identified.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 5…

Full details: Docstring Coverage

Explanation

No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 5 files.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[lordrip]

Thanks for the contribution @etzel-mes 👍

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[lhein]

Thank you, @etzel-mes