Name the macro slot count

Three loops walked 1..36 by hand, two of them re-arguing in comments why 36
is the right number. It is: the client addresses 18 account-wide macros at
1-18 and 18 character-specific ones at 19-36, and that range is what
GetMacroInfo and C_Macro.SetMacroDisplay index. Nothing in the API hands it
back -- GetNumMacros() returns how many of each tab are used, which cannot be
summed into a range, because the character block still starts at 19 when the
account block is empty. Blizzard's MAX_MACROS is no better: it lives in the
load-on-demand Blizzard_MacroUI and is nil until the macro window is opened.

So CleveRoids.MAX_MACRO_SLOTS in Init.lua, carrying that reasoning once.
ValidateAllMacros also dropped a numAccountMacros it computed and never read.

ReleaseDisplays keeps sweeping the full range rather than the macros it knows
it published: PublishAllDisplays clears that record on each re-parse, so a
macro claimed before one and gone after it would keep our last published value
forever. Releasing a slot we never claimed costs nothing, and it runs once.

MacroErrorChecker.lua

@@ -1096,17 +1096,7 @@ function CleveRoids.ValidateAllMacros()
     local results = {}
     local totalErrors = 0
 
-    -- Account-wide macros are indexed from 1 up to GetNumMacros().
-    -- Character-specific macros occupy the slots immediately following the account-wide ones.
-    -- In Classic clients, the macro UI has 18 General (Account) slots and 18 Character-Specific slots.
-    local numAccountMacros = GetNumMacros()
-
-    -- The WoW API GetMacroInfo(index) supports indexing up to 36 (1-18 for General, 19-36 for Character)
-    -- in Classic clients, even though the total is GetNumMacros() + GetNumCharacterMacros() in Retail.
-    -- To ensure we check all 36 possible slots:
-    local totalSlots = 36
-
-    for i = 1, totalSlots do
+    for i = 1, CleveRoids.MAX_MACRO_SLOTS do
         local nameSuccess, name = pcall(GetMacroInfo, i)
 
         -- Check if GetMacroInfo returned a name (i.e., the slot is used)