Attempt to fix: font not set error when cast bars are enabled

[monolitas]

**bug fix for: #482
When cast bars are enabled, the UI throws a "SetText" error

[Copilot]

Pull Request Overview

This PR fixes a "Font not set" error that occurs when cast bars are enabled in the nameplate module during initialization. The fix adds safeguards to ensure fonts are properly set before attempting to display text on cast bar elements.

• Adds conditional logic to only manipulate test cast bars when any cast bar is enabled in settings
• Implements font validation and fallback assignment before setting text
• Adds nil checks for cast bar elements before accessing their properties

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[Copilot]

The repeated pattern for checking castbar.enable across different unit types creates duplicated logic. Consider extracting this into a helper function or using a loop over unit types to reduce code duplication.

Suggested change

	local anyCastbarEnabled = unitsDB and (
	(unitsDB.ENEMY_PLAYER and unitsDB.ENEMY_PLAYER.castbar and unitsDB.ENEMY_PLAYER.castbar.enable) or
	(unitsDB.ENEMY_NPC and unitsDB.ENEMY_NPC.castbar and unitsDB.ENEMY_NPC.castbar.enable) or
	(unitsDB.FRIENDLY_PLAYER and unitsDB.FRIENDLY_PLAYER.castbar and unitsDB.FRIENDLY_PLAYER.castbar.enable) or
	(unitsDB.FRIENDLY_NPC and unitsDB.FRIENDLY_NPC.castbar and unitsDB.FRIENDLY_NPC.castbar.enable)
	) or false
	local unitTypes = { "ENEMY_PLAYER", "ENEMY_NPC", "FRIENDLY_PLAYER", "FRIENDLY_NPC" }
	local anyCastbarEnabled = false
	if unitsDB then
	for _, unitType in ipairs(unitTypes) do
	local unit = unitsDB[unitType]
	if unit and unit.castbar and unit.castbar.enable then
	anyCastbarEnabled = true
	break
	end
	end
	end

[Copilot]

The font checking and setting logic is duplicated for both Name and Time elements. This could be extracted into a helper function that takes the text element as a parameter to reduce code duplication.

Suggested change

	if castbar.Name and not select(1, castbar.Name:GetFont()) then
	castbar.Name:SetFontObject(GameFontNormal)
	end
	if castbar.Time and not select(1, castbar.Time:GetFont()) then
	castbar.Time:SetFontObject(GameFontNormal)
	end
	local function EnsureFontSet(textElement)
	if textElement and not select(1, textElement:GetFont()) then
	textElement:SetFontObject(GameFontNormal)
	end
	end
	EnsureFontSet(castbar.Name)
	EnsureFontSet(castbar.Time)