Update README with clarification on loop unrolling

[ewdlop]

Clarify the discussion on loop unrolling in the context of performance gains.

[Copilot]

Pull Request Overview

This PR adds a clarifying comment to the README documentation about loop unrolling in the context of premature optimization pitfalls. The change seeks to improve the explanation of when loop unrolling may not be beneficial.

• Added a clarifying comment to the loop unrolling example

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[Copilot]

The inline comment '<--- not yielding?' is unclear and appears to be a draft note rather than proper documentation. Consider either removing it or expanding it into a clearer explanation about when loop unrolling doesn't yield performance benefits.

Suggested change

	- **Loop Unrolling**: Manually unrolling loops in the hopes of performance gains, even when the loop is not a bottleneck. <--- not yielding?
	- **Loop Unrolling**: Manually unrolling loops in the hopes of performance gains, even when the loop is not a bottleneck. This often does not yield significant performance improvements unless the loop is a proven bottleneck and the compiler cannot optimize it automatically.