Marketplace and external add-ons disable achievements after the latest update

**Steps to reproduce:**

1. Create or open a pure Survival world (achievements enabled).

2. Activate any marketplace add-on or a verified external behavior pack that doesn't require experiments or cheats.

3. Enter the world settings.

**Observed results:**

The game shows the "Achievements cannot be earned in this world" message, treating the world as if cheats or creative mode were active. This started happening right after the latest update (Wilderness Bound / 26.51 update).

**Expected results:**

Valid marketplace and external add-ons should keep achievements enabled as intended by official gu

idelines.