custom items and blocks (blocks are broken in 1.17) that are from .mcaddons do not show up in the creative inventory or in the recipe book like custom blocks from older versions

Edit:

Both items, and blocks now show up in the creative inventory. Make sure to include the minecraft:creative_category component.

Steps to Reproduce:

1. Download the example addon below
2. install it how you would install all other addons (click on it for windows 10)
3. create a new world
4. make sure experimental gameplay is turned on. (holiday creator features)
5. activate the resourcepack and behavior pack
6. finish creating your world

Observed Results:

• Custom items/blocks can be received by '/give @s custom:sample_item' and/or '/give @s custom:sample_block'
• The recipe is not shown in the recipe book like vanilla items/blocks (both players, and crafting table)
• Items are not shown in the creative inventory.
• Blocks do not show up in the creative inventory.

Expected Results:

• Items and blocks can be received in creative inventory
• Item and block recipes will be shown in the recipe book (both players, and crafting table)