Resolve item sets via ClassicAPI; drop Reliquary dependency

Item-set membership and set info now read ItemSet.dbc directly through
ClassicAPI instead of the nampower/Reliquary glue, so set features no
longer require the Reliquary DLL to be installed.

- ClassicAPI.lua: add GetItemSetIDByID and GetItemSetInfo wrappers.
- Utility.lua: repoint ResolveSetItems, CountEquippedSetItemsBySetId,
  GetEquippedItemSetInfo, and GetEquippedSetPieceCount at the ClassicAPI
  accessors. Set-name matching now uses the DBC name (localized; identical
  to the old enUS path on English clients).
- NampowerAPI.lua: remove the now-unused GetItemSet/GetItemSetId/
  GetItemSetItems/GetItemSetBonuses, the dead GetSpellEffectRadius (no
  callers, only radius source was Reliquary), and the orphaned RQ_SafeCall.
- Init.lua: drop hasReliquary detection and its startup feature line.
- Conditionals.lua: update the [set:] comment (no longer Reliquary-gated).

Conditionals.lua

@@ -5751,8 +5751,8 @@ CleveRoids.Keywords = {
 
     -- [set:SetName>=N] — true if equipped piece count of named set meets comparison
     -- [set:SetName] — true if any pieces of that set are equipped (count > 0)
-    -- [set:123>=3] — numeric IDs also supported (Nampower only, no Reliquary needed)
-    -- Name lookup requires Reliquary (for DBC set name); ID lookup requires Nampower
+    -- [set:123>=3] — numeric IDs also supported
+    -- Both name and ID lookups resolve from ItemSet.dbc via ClassicAPI
     set = function(conditionals)
         return Multi(conditionals.set, function(args)
             if type(args) == "table" and args.operator and args.amount then