Fix #5222, #5223, #5224: Wire missing element getter/setter types

[x6c85]

Summary

getElementAlpha / setElementAlpha, isElementFrozen / setElementFrozen and getElementCollisionsEnabled were missing building, weapon and projectile in their type switches, so they returned false even when the matching setter already worked.

• Buildings: alpha and collisions getter
• Weapons: collisions getter and frozen get/set (CClientWeapon already inherits object alpha)
• Projectiles: alpha and frozen get/set

Motivation

Fixes #5222, #5223 and #5224. crun b = createBuilding(1337, me.position) then b.alpha / getElementCollisionsEnabled(b) returned false. createProjectile then p.frozen / p.frozen = true also returned false.

Test plan

1. crun b = createBuilding(1337, me.position) then getElementCollisionsEnabled(b) is true; b.alpha is 255; b.alpha = 0 returns true and the building goes invisible.
2. crun setElementCollisionsEnabled(b, false) then getElementCollisionsEnabled(b) is false.
3. Create a custom weapon: getElementCollisionsEnabled matches the setter; isElementFrozen / setElementFrozen work.
4. crun p = createProjectile(me, 16, me.position, 1.0) setProjectileCounter(p, 3000) then p.alpha / p.alpha = 0 and p.frozen = true return the real values, not false.
5. Existing ped/vehicle/object alpha, frozen and collisions unchanged.

Checklist

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