fix(linter): Make extended configs properly inherit plugins

[zubhav]

Fixes #10173

When extending configuration files in Oxlint, plugins from the extended config were not being properly inherited, which caused rules requiring those plugins to be filtered out. This was encountered in issue #10173 where rules like vitest/no-focused-tests were being ignored even when the vitest plugin was defined in a base configuration.

The issue occurred because in the implementation of from_oxlintrc. The following changes were made:

Modified plugin inheritance logic in from_oxlintrc:

• Now checks if the child configuration has explicitly specified plugins
• If the child has default plugins (not explicitly specified), it inherits from the parent
• If the child has explicitly specified plugins, it combines them with the parent's plugins (like ESLint)
• Empty plugin arrays are treated as explicit specifications

Added tests to verify the behavior:

• Tests for empty configurations
• Tests for configurations with empty plugin arrays
• Tests for configurations with explicitly specified plugins
• Tests for configurations that extend other configurations

This ensures that when rules are added from an extended config, the necessary plugins are already enabled, so the rules won't be filtered out in the build step.

cc @camchenry

[graphite-app]

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[camchenry]

Haven't had a chance to review this yet, but I will take a look next time I am able.

[camchenry]

These tests look good, but let's refactor it to not need an extra dependency, to help keep things simpler

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #10174 will not alter performance

_{Comparing zubhav:fix-10173-extended-config-plugin-inheritance (08aa912) with main (81867c4)}

Summary

✅ 36 untouched benchmarks

[zubhav]

@camchenry Could you also take a look at #10157 please? Its another fix for nested config

[camchenry]

Thank you for the updates!

[graphite-app]

Merge activity

• Apr 8, 12:00 AM EDT: @zubhav we removed the merge queue label because we could not find a Graphite account associated with your GitHub profile.

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• Apr 9, 12:39 AM EDT: @zubhav we removed the merge queue label because we could not find a Graphite account associated with your GitHub profile.

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[zubhav]

@camchenry Could you help with the graphite-app comment above? I've configured the account so I'm guessing we'll need to re-add the label. Thanks!