Fix setElementDimension not working on buildings

[TheCrazy17]

Summary

CClientBuilding extends CClientEntity directly, not CClientStreamElement, so unlike objects, peds and vehicles it never got automatic dimension-based streaming; SetDimension only stored the value, nothing ever compared it to the local player's dimension to actually show or hide the building.

Added the same RelateDimension pattern already used by CClientPointLights, CClientRadarArea, CClientRadarMarker and CClientWater, the other element types that also aren't stream elements: CClientBuildingManager tracks the local player's dimension and calls RelateDimension on every building when it changes; CClientBuilding overrides SetDimension to re-evaluate itself the same way. Also fixed RestoreDestroyed(), which recreated every building unconditionally on pool resize, ignoring dimension entirely.

Motivation

setElementDimension silently did nothing on buildings; scripts had no way to hide a createBuilding building in a different dimension.

Test plan

Created a building, moved the local player between dimensions and called setElementDimension on the building both ways: it now shows only when its dimension matches the player's, and correctly disappears/reappears when either side changes.

Checklist

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