Add muddy mangrove roots

overviewer_core/src/mc_id.h

@@ -411,6 +411,7 @@ enum mc_block_id {
     block_mud_brick_slab = 1124,
     block_mangrove_roots = 1125,
     block_mangrove_log = 1126,
+    block_muddy_mangrove_roots = 1127,
 
     // adding a gap in the numbering of walls to keep them all
     // in one numbering block starting at 1792