Move permission checks DLL-side: canSetMarkers, senderHasPermission, senderInGroup

Replace Lua-side permission checks with direct memory reads in the DLL.
All marker mutation functions now verify sender identity against the
raid roster / party leader GUID without touching Lua state.

- Add getPlayerGUID (0x468550), getNameFromGUID (name cache at 0xc0e228)
- Add canSetMarkers: checks local player is leader/officer via roster
- Add senderHasPermission: verifies sender name against roster ranks
- Add senderInGroup: weaker check for sync relay (any rank)
- WorldMarker/ClearWorldMarker return 1/nil for addon feedback
- SetMarkerDef/ClearMarkerDef take sender name param, verify DLL-side
- SetMarkerDefSync: dual check (local=leader + sender in group)
- CanSetMarkers() Lua function for addon broadcast decisions
- Remove Lua-side canSetMarkers/senderHasPermission from Markers.lua
- Add offsets: LEADER_GUID, RAID_ROSTER_ARRAY, RAID_MEMBER_COUNT, etc.

src/main.zig

@@ -111,12 +111,12 @@ fn registerLuaFunctions() void {
     if (build_opts.markers and markers.isActive()) {
         registerFunction("WorldMarker", @intFromPtr(&markers.luaWorldMarker));
         registerFunction("ClearWorldMarker", @intFromPtr(&markers.luaClearWorldMarker));
-        registerFunction("GetPlayerPosition", @intFromPtr(&markers.luaGetPlayerPosition));
-        registerFunction("DistanceToMark", @intFromPtr(&markers.luaDistanceToMark));
         registerFunction("SetMarkerDef", @intFromPtr(&markers.luaSetMarkerDef));
+        registerFunction("SetMarkerDefSync", @intFromPtr(&markers.luaSetMarkerDefSync));
         registerFunction("ClearMarkerDef", @intFromPtr(&markers.luaClearMarkerDef));
         registerFunction("GetMarkerDef", @intFromPtr(&markers.luaGetMarkerDef));
         registerFunction("GetCurrentAreaId", @intFromPtr(&markers.luaGetCurrentAreaId));
+        registerFunction("CanSetMarkers", @intFromPtr(&markers.luaCanSetMarkers));
     }
 }