fix: enable stance/state bars for CoA custom classes with shapeshift forms

Vanilla Bartender4 assumes only DRUID/WARRIOR/WARLOCK/PRIEST/ROGUE/HERO have
shapeshift forms. CoA custom classes (Witchdoctor, Templar, …) can register
forms late at runtime and aren't in the whitelist, so the stance/state bar
never came up for them.

StanceBar.lua:
  - ApplyConfig() no longer Disable()s the module when GetNumShapeshiftForms()
    is 0 at config time. A disabled module never re-enables on
    UPDATE_SHAPESHIFT_FORMS, so late-registered forms were lost. We now just
    hide the bar frame.
  - Register UPDATE_SHAPESHIFT_FORMS and PLAYER_ENTERING_WORLD on the module
    itself and re-Enable() / show the bar when forms appear after the fact.

Options/Bar.lua:
  - The 'Hide in Stance/Form' visibility option was gated by a hard-coded
    stanceClasses whitelist. Add an OR-fallback on GetNumShapeshiftForms() > 0
    so CoA classes with forms get the UI.

StateBar.lua:
  - DefaultStanceMap only had vanilla entries. For unknown classes with live
    forms, synthesise a generic { id="formN", index=N } map at runtime so
    UpdateStates() can wire stance-based action bar swaps.

Bartender4/StateBar.lua

@@ -116,12 +116,34 @@ local DefaultStanceMap = setmetatable({}, { __index = function(t,k)
 end})
 Bartender4.StanceMap = DefaultStanceMap
 
+-- CoA: build a generic runtime stance map for classes the addon doesn't know
+-- about (Witchdoctor, Templar, …). We don't have spell-id metadata for them,
+-- so synthesise { id = "formN", index = N } entries based on live form count.
+local function BuildGenericStanceMap()
+	local num = GetNumShapeshiftForms()
+	if not num or num == 0 then return nil end
+	local map = {}
+	for i = 1, num do
+		map[i] = { id = ("form%d"):format(i), name = ("Form %d"):format(i), index = i }
+	end
+	return map
+end
+
 local stancemap
 function StateBar:UpdateStates(returnOnly)
 	if not self.buttons then return end
 	self.statebutton = {}
-	if not stancemap and DefaultStanceMap[playerclass] then
-		stancemap = DefaultStanceMap[playerclass]
+	-- CoA: rebuild generic stance maps each call so late-registered forms get
+	-- picked up; vanilla classes keep their cached DefaultStanceMap entry.
+	if not stancemap then
+		if DefaultStanceMap[playerclass] then
+			stancemap = DefaultStanceMap[playerclass]
+		elseif GetNumShapeshiftForms() > 0 then
+			stancemap = BuildGenericStanceMap()
+		end
+	elseif not DefaultStanceMap[playerclass] then
+		-- generic map: refresh on every call in case form count changed
+		stancemap = BuildGenericStanceMap()
 	end
 
 	local statedriver