Fix Pause to Pause-UI in script and update docs for v3

[GhostwheeI]

Fixed code usages of Pause in WindowsUpdate-Manager.ps1 changing them to use the defined function Pause-UI. Removed duplicate Pause-UI function. Corrected README.md and USER_GUIDE.md files to note Version 3 properly including visual notes.

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PR created automatically by Jules for task 4284120944198178170 started by @GhostwheeI

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