No new advancements/achievements added related to the Copper Golem or Shelves.

As previous game drops (e.g., Armored Paws, The Garden Awakens, Chase the Skies) usually had their own advancements come with features (e.g., The Whole Pack, Heart Transplanter (got added later, but still counts towards the "The Garden Awakens" drop) as well as the "Stay Hydrated!") it seems odd (hence the bug report and not a feature suggestion) that no new advancements got introduced for the "The Copper Age" game drop.

Meaning there's no advancements requiring the player to do anything with the Copper Golem nor the new Shelves. So a simple advancement like swapping your entire hotbar using Shelves would make sense and something similar for the Copper Golem (e.g., putting down a Copper Chest with a Hopper and a Chest above, then Copper Golems pick up items from the Copper Chest and put them into the regular Chest at the top, creating this infinite cycle). So players get a "reward" for making use of the new features. This also applies to achievements for the Bedrock Edition of the game.