Allow to override project list

[joaquimrocha]

Summary

This PR allows plugins to override the list of projects, so they can implement projects however they like and they can list them in the project list.

Steps to Test

1. Check out the example in the project example plugin

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: joaquimrocha

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[k8s-ci-robot]

PR needs rebase.

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[Copilot]

Pull Request Overview

This PR implements a plugin system that allows customization of the project list discovery mechanism. Plugins can now register processors to extend, filter, or completely override how projects are discovered and displayed.

Key changes:

• Introduces ProjectListProcessor functionality with registration mechanism
• Makes project details tab icons optional to improve API flexibility
• Provides example implementation showing how to extend project lists with custom projects

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
plugins/headlamp-plugin/src/index.ts	Exports new project list processor types and registration function
plugins/examples/projects/src/index.tsx	Demonstrates project list processor usage and fixes property references
plugins/examples/projects/README.md	Documents the new project list processor feature
frontend/src/redux/projectsSlice.ts	Implements Redux state management for project list processors
frontend/src/plugin/registry.tsx	Adds registration function for project list processors
frontend/src/components/project/ProjectList.tsx	Integrates processor execution into project discovery logic
frontend/src/components/project/ProjectDetails.tsx	Handles optional icons in project details tabs

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[Copilot]

Debug console.log statement should be removed from production code.

Suggested change

console.log('Final projects:', projects);

[Copilot]

Using Date.now() for ID generation could create duplicate IDs if multiple processors are registered simultaneously. Consider using crypto.randomUUID() or a counter-based approach for guaranteed uniqueness.

[Copilot]

Using Date.now() for ID generation could create duplicate IDs if multiple processors are registered simultaneously. Consider using crypto.randomUUID() or a counter-based approach for guaranteed uniqueness.

Suggested change

	id: `generated-id-${Date.now().toString(36)}`,
	processor: action.payload,
	};
	}
	if (!processor.id) {
	processor.id = `generated-id-${Date.now().toString(36)}`;
	id: `generated-id-${crypto.randomUUID()}`,
	processor: action.payload,
	};
	}
	if (!processor.id) {
	processor.id = `generated-id-${crypto.randomUUID()}`;