Ported Luau documentation for vector library to the Roblox documentation

[010DevX101]

Changes

The Luau team has recently developed and added to the Luau documentation a new vector library, although this change has not been reflected into the Roblox Creator Documentation. To avoid potential confusion for developers who encounter a new undocumented library, I've decided to port the Luau vector documentation, with minimal changes (only omitting features not available in the Roblox environment such as 4-wide mode) to keep it concise and accurate to the Roblox environment.

Checks

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[CadeusTheGreat]

Thank you for raising this PR, if it gets merged I will add it as a reference to my changes in #943

[010DevX101]

Updated branch to the latest version.

[IgnisRBX]

Thanks for the commit! Once this gets released live, I'll make a separate PR to include it in the left-side TOC on the Docs site alongside the other libraries.