Add tests for vector syntaxes

[sovdeeth]

Description

Adds tests for all vector-related syntaxes. Fixes up some docs/pattern issues with assorted vector syntaxes as well.

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Target Minecraft Versions: any Requirements: none Related Issues: #6158

[Moderocky]

Looking good so far, I'm ticking off all the ones you make so that nobody else makes the same.

[Moderocky]

As far as I can see, the remaining ones are:

• [x] ExprLocationFromVector
• [x] ExprVectorFromYawAndPitch
• [x] ExprLocationVectorOffset
• [x] ExprVectorNormalize
• [x] ExprVectorSquaredLength
• [x] ExprVectorOfLocation
• [x] ExprVectorSpherical
• [x] ExprVectorXYZ
• [x] ExprVectorLength

then

• [x] CondIsVectorNormalized

and

• [x] EffVectorRotateAroundAnother
• [x] EffVectorRotateXYZ