feat: add vue/no-duplicate-class-names rule

[Yizack]

resolves #2932

[changeset-bot]

🦋 Changeset detected

Latest commit: fde5af0

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
eslint-plugin-vue	Minor

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[Yizack]

I believe this rule is now ready!

[FloEdelmann]

Thanks for your contribution! Sorry that reviewing took so long. I only have a few small suggestions/requests; in general the code looks really good! 🙂

[Yizack]

Thanks for your contribution! Sorry that reviewing took so long. I only have a few small suggestions/requests; in general the code looks really good! 🙂

Hi! No problem, thanks for the review 🙂, I just applied your suggestions and requests

[FloEdelmann]

Looks good to me 🙂
Thank you! 🥳

[Copilot]

Pull Request Overview

This PR adds a new ESLint rule vue/no-duplicate-class-names that detects and automatically fixes duplicate class names in Vue template class attributes and directives.

Key changes:

• Implements comprehensive duplicate class detection across static attributes, dynamic bindings, arrays, objects, conditionals, and binary expressions
• Provides automatic fixing that preserves original spacing when removing duplicates
• Detects duplicates both within single attributes and across static/dynamic class attributes

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
lib/rules/no-duplicate-class-names.js	Core rule implementation with duplicate detection logic and auto-fix functionality
tests/lib/rules/no-duplicate-class-names.js	Comprehensive test suite covering valid/invalid cases and various class binding patterns
lib/index.js	Registers the new rule in the plugin's rule index
docs/rules/no-duplicate-class-names.md	User-facing documentation with examples and usage guidance
docs/rules/index.md	Updates rule listing to include the new rule
.changeset/ten-lines-fail.md	Changelog entry for the new feature

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