Remove remaining items in the unified plugin used for legacy config compatibility and simplify plugin export

[Rel1cx]

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• Bugfix
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• Code style update
• Refactor
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Does this PR introduce a breaking change?

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Project	Deployment	Preview	Comments	Updated (UTC)
eslint-react	Ready	Preview	Comment	Oct 14, 2025 9:26am

[Copilot]

Pull Request Overview

Refactor to remove internal transform utilities and streamline the ESLint plugin export by simplifying the rules and typing of configs.

• Remove unused transform utilities (type-of, transform-keys, pad-keys-left) and their barrel export.
• Simplify plugin export to only include react-x rules and inline the configs into the exported plugin object.
• Add a typed ConfigName union and narrow the plugin's configs type.

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/plugins/eslint-plugin/src/utils/type-of.ts	Removed helper used only by transform utilities.
packages/plugins/eslint-plugin/src/utils/transform-keys.ts	Removed key transformation utility.
packages/plugins/eslint-plugin/src/utils/pad-keys-left.ts	Removed left-padding keys utility previously used to prefix external plugin rules.
packages/plugins/eslint-plugin/src/utils/index.ts	Removed utils barrel export.
packages/plugins/eslint-plugin/src/index.ts	Simplified plugin export, narrowed config typing, and removed prefixed external plugin rules from rules.

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