feat(linter/vue): implement return-in-emits-validator rule

[babu-ch]

related #11440

upstream: https://eslint.vuejs.org/rules/return-in-emits-validator.html

AI disclosure: implemented with Claude Code, reviewed manually.

[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 47 skipped benchmarks¹

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_{Comparing babu-ch:feat/vue-return-in-emits-validator (eef588e) with main (2d5fc16)}

Footnotes

1. 47 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. ↩