fix(linter/no-array-index-key): false positive when index is inside an expression within a template literal

[babu-ch]

Closes #21110

Related: #21012

Summary

The TemplateLiteral branch in expression_uses_index was calling expression_uses_index recursively, so it detected index even when wrapped in a binary expression or function call inside ${...}. ESLint only checks for direct index references, so replaced with is_index_reference.

ESLint comparison (inside template literals)

Pattern	ESLint	oxlint (before)	oxlint (after)
`abc${index}`	error	error	error
`${item.type + index}`	pass	error	pass
`abc${String(index)}`	pass	error	pass
`abc${index.toString()}`	pass	error	pass

[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 47 skipped benchmarks¹

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_{Comparing babu-ch:fix/no-array-index-key-template-literal-false-positive (7eefd29) with main (15574bc)}

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. ↩

[camc314]

Thanks!