feat(linter): add eslint/no-unassigned-vars rule

[huangtiandi1999]

Rule detail: https://eslint.org/docs/latest/rules/no-unassigned-vars

[graphite-app]

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #11365 will improve performances by 3.01%

_{Comparing huangtiandi1999:feat/linter/no-unassigned-vars (ae8b865) with main (ffcfb46)}

Summary

⚡ 1 improvements
✅ 33 untouched benchmarks
⁉️ 4 dropped benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⁉️	linter[RadixUIAdoptionSection.jsx]	2.8 ms	N/A	N/A
⁉️	linter[binder.ts]	148.5 ms	N/A	N/A
⁉️	linter[cal.com.tsx]	1.3 s	N/A	N/A
⁉️	linter[react.development.js]	54.4 ms	N/A	N/A
⚡	mangler[cal.com.tsx]	3 ms	3 ms	+3.01%