refactor(linter/plugins): simplify ser/deser of ExternalPluginEntry

[overlookmotel]

Follow-on after #15569. Simplify serialization/deserialization of ExternalPluginEntry. Since we now have a type for this, there's no need for deserialize_external_plugins any more.

[overlookmotel]

• refactor(linter/plugins): simplify ser/deser of ExternalPluginEntry #17019 👈 (View in Graphite)
• fix(linter/plugins): fix indentation in error message #17018
• main

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[Copilot]

Pull request overview

This PR refactors the serialization and deserialization of ExternalPluginEntry to simplify the code by removing the custom deserialize_external_plugins function. The refactoring leverages serde's built-in support for deserializing Option<FxHashSet<T>> where T implements Deserialize, since ExternalPluginEntry already has a custom Deserialize implementation that handles both string and object formats.

Key changes:

• Removed the deserialize_external_plugins function and its associated visitor logic
• Simplified serde attributes on fields using external_plugins by removing the custom deserialize_with parameter
• Updated imports to remove unused references to the removed function
• Cleaned up unused imports (fmt, rustc_hash::FxHashSet from the main module)

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
crates/oxc_linter/src/config/external_plugins.rs	Removed deserialize_external_plugins function and unnecessary imports; improved documentation comments for the ExternalPluginEntry ser/deser implementations; simplified test configurations to use default serde behavior
crates/oxc_linter/src/config/oxlintrc.rs	Removed deserialize_external_plugins from imports and simplified serde attributes on the external_plugins field
crates/oxc_linter/src/config/overrides.rs	Removed deserialize_external_plugins from imports and simplified serde attributes on the external_plugins field

The refactoring is well-tested and maintains the same behavior as before while reducing code complexity. No issues were identified during the review.

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[codspeed-hq]

CodSpeed Performance Report

Merging #17019 will not alter performance

_{Comparing 12-17-refactor_linter_plugins_simplify_ser_deser_of_externalpluginentry_ (a6004b2) with main (674dab9)}

Summary

✅ 4 untouched
⏩ 41 skipped¹

Footnotes

1. 41 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[camc314]

Merge activity

• Dec 17, 11:08 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 17, 11:08 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Dec 17, 11:14 PM UTC: Merged by the Graphite merge queue.