Hide lag bar for invalid conditions

For some interactables, such as specific quest-related objects in WoD, we never receive a SpellCastSent event, only a SpellCastStart. If, prior to that event, we ever failed a spell cast, we would have an outdated "spell sent time" saved off for a previous cast. This value would then get used due to us receiving a Start with no Sent and would cause the lag bar to fill the entire cast bar incorrectly. For these cases, we now no longer show the lag bar at all because we don't receive enough information from the game to compute one.

modules/CastBar.lua

@@ -4,7 +4,7 @@ local CastBar = IceCore_CreateClass(IceCastBar)
 local IceHUD = _G.IceHUD
 
 CastBar.prototype.spellCastSent = nil
-
+CastBar.prototype.sentSpell = nil
 
 -- Constructor --
 function CastBar.prototype:init()
@@ -409,6 +409,7 @@ function CastBar.prototype:SpellCastSent(event, unit, spell, rank, target)
 	if (unit ~= self.unit) then return end
 
 	self.spellCastSent = GetTime()
+	self.sentSpell = spell
 end
 
 -- OVERRIDE
@@ -420,6 +421,10 @@ function CastBar.prototype:SpellCastStart(event, unit, spell, rank)
 		return
 	end
 
+	if self.sentSpell ~= spell then
+		self.spellCastSent = nil
+	end
+
 	local scale
 	if self.unit == "vehicle" then
 		scale = 0