Update CocoaPods guidance to reflect current version

[kevnm67]

Description

Updated the CocoaPods optimization section to remove outdated version references and reflect the current CocoaPods version shipped in the macOS image.

Reasons

The existing guidance cited CocoaPods 1.8 as the minimum recommended version, which is outdated. Updated the copy to reflect the current version shipped in the Xcode 26.3.0 image (1.16.2) so contributors have an accurate, up-to-date reference.

Content checks

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Content structure:

• Break up walls of text by adding paragraph breaks.
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